Table of Contents publications...Anthony currently serves as Co-Chair of the IABPA Certification...

Table of Contents

2013 IABPA Officers 1

President’s Message 2

2013 IABPA Executive Board Introductions 3

TECHNICAL PAPER: The Development and Construction

of a Motorized Blood Droplet Generation Device (BDGD)

for Detailed Analysis of Blood Droplet Dynamics

Elizabeth Williams and Michael Taylor 14

Recent BPA Articles in the Scientific Literature 30

Organizational Notices 31

Training Opportunities 32

Editor’s Corner 36

Publication Committee/Associate Editors 37

Past Editors of the IABPA News/Journal of Bloodstain

Pattern Analysis 37

Past Presidents of the IABPA 37

Journal of Bloodstain Pattern Analysis 1 Vol. 29 No. 1 March 2013

2013 IABPA Officers

PRESIDENT

Patrick Laturnus [email protected]

Vice President - Region I Vice President - Region II

Pacific Mountain

Don Schuessler Leah Innocci [email protected] [email protected]

Vice President - Region III Vice President, Region IV

Central Eastern

Rex T. Sparks Anthony Mangione [email protected] [email protected]

Vice President - Region V Vice President - Region VI

European Pacific Rim

Peter Lamb Brett McCance

[email protected] [email protected]

Secretary / Treasurer Sergeant at Arms

Norman Reeves Jeffrey Scozzafava [email protected] [email protected]

Immediate Past President Historian

Todd A. Thorne Stuart H. James [email protected] [email protected]

mailto:[email protected]




President’s Message

We’re in our 30

th year as the most influential organization in Bloodstain Pattern Analysis.

Our charter members gathered in November of 1983 and look at where we are today. I’m so pleased and proud to be your President in 2013. Look at us now; we’ve come a long way… from smoke and mirrors to empirical scientific evidence.

In keeping with our tradition, the 2013 IABPA Training Conference in San Diego promises to be a great educational event at a fantastic venue. Carolyn Gannett and Lisa DiMeo are working hard to make this year’s conference not only worthwhile but memorable. Please contact them with your presentation ideas; we’re all looking forward to hearing from you.

The first impression I had of this organization was how helpful and open its members were. At my first meeting (and ever since then), I’ve made contacts with not only leaders in the field but also people who were interested in what I had to say. The strength of these contacts provided a level of confidence that allowed me to venture into bloodstain pattern analysis uninhibited. If you are a member of the IABPA, we hope that you will take advantage of our incredible resources. If you are interested in BPA, we hope that you will join us in maintaining one of the most helpful tools in forensics today.

Our members will note that the IABPA website now includes both current and back issues of the Journal. This excellent reference material continues to grow and through current research the published information lays a foundation for credible opinions. Please continue to support the Journal, not only by reading but also by contributing. Your ideas are important. Many thanks to Stuart James, our Editor.

The website gets a lot of hits during the day and we’re grateful for the amount of work that it takes to keep it going. Please recommend it to anyone getting into the discipline and as a member, use the member’s only area to your advantage. Many thanks to Joe Slemko, our Webmaster. I’m joined by an active executive board dedicated to not only maintaining our image but also to improve the way we interact. We receive your inquires with great interest and satisfaction that the system is working. Please don’t hesitate to contact us for any reason. We are prepared to listen and to put new ideas or improvements on the agenda for our San Diego meeting. On behalf of the IAPBA Executive Board, enjoy this edition of the Journal. Come on down to San Diego, we can’t wait to see you again or for the first time. Pat Laturnus President IABPA


2013 IABPA EXECUTIVE BOARD INTRODUCTIONS

President

Patrick Laturnus Pat is presently working as a private consultant in Ottawa, Ontario Canada. He started his

forensic career with the RCMP in 1975 and went on to become a Bloodstain Analyst in 1990. He has always enjoyed opportunities to instruct and subsequently went on to be a full time instructor. During that time Pat developed an understudy program based on his training. This program has certified people as qualified bloodstain analysts not only in Ontario, but across Canada and Internationally.

His career has taken him across Canada where he’s worked in 8 of the 10 Provinces. During this time he’s been accepted as an expert witness in: Bloodstain Pattern Analysis, Fingerprint Identification and Physical Comparisons. In addition he has taught and continues to teach Bloodstain Pattern Analysis on an International basis.

He has written several bloodstain related articles and has appeared on radio and television. Pat is the proud recipient of awards from the Provincial Government of Ontario (Amethyst and Ovation), as well as winner of the Foster Award which is the highest honor bestowed by the Canadian Identification Society. One of his most proud occasions came when he was also awarded the honor of "Distinguished Member" of the International Association of Bloodstain Pattern Analysts.

Since becoming a member of the IAPBA in 1990, he has benefited greatly by attending conferences and meeting fellow bloodstain analysts. He has participated through support and attendance, as well as serving as a Vice-President and an Ethics committee member.


Vice President, Region I

Pacific

Donald R. Schuessler, MS, CBPE

Donald has over thirty years’ experience in forensics, latent print examination and expert witness testimony He retired from full time employment with the Eugene Police Department Forensic Evidence Unit in 2005. Through his work as a Forensic Analyst and Deputy Medical Examiner Investigator he has developed strong technical skills in all phases of crime scene/death investigation and physical evidence examination. Don is a Charter Member of the International Association of Bloodstain Pattern Analysts served its first Secretary Treasurer and currently as the Co-Chair of the Certification Committee. Don has contributed to four text books written on the subject of bloodstain pattern analysis/crime scene reconstruction and has published articles in professional journals and newsletters such as the FBI’s Crime Laboratory Digest and IABPA Newsletter. He obtained certification as a Bloodstain Pattern Examiner through the International Association for Identification and currently is the only individual to hold that certification in the State of Oregon.


Vice President - Region II

Mountain

Leah Innocci

Leah Innocci is a forensic scientist for the Wyoming State Crime Laboratory, serving the

criminal justice system for the state of Wyoming. She specializes in bloodstain pattern analysis, latent fingerprint analysis, and crime scene Investigation. In addition to her duties as IABPA Region II Vice-President, Leah has served as the Chair of the Education Committee as well as Vice-President and President of the Rocky Mountain Association of Bloodstain Pattern Analysts (RMABPA). She serves as a member of the Training and Education Committee for the Scientific Working Group on Bloodstain Pattern Analysis (SWGSTAIN). She is a member of the International Association for Identification (IAI) and the Rocky Mountain Division of the IAI. She has taught several classes in crime scene management at the Wyoming Law Enforcement Academy.

Leah received her Associate’s degree in May 2010 from Laramie County Community College and is currently working toward her Bachelor’s degree, majoring in Criminal Justice with a Concentration in Pre-Forensic Science. Leah is a proud veteran of the United States Army where she served as a Medical Laboratory Technician. She lives in Cheyenne with her husband and three beautiful daughters.


Vice President - Region III

Central

Rex T. Sparks

Rex T. Sparks has a thirty seven year career in forensic science and crime scene processing

that began with the Story County, Iowa Sheriff’s Department. He is currently an Identification Technician with the Des Moines, Iowa Police Department as well as a private forensic consultant and also instructs forensic courses. He has a total of over 1800 hours of training in forensic disciplines including bloodstain pattern analysis, crime scene and shooting reconstruction, photography and advanced crime scene technology. Mr. Sparks has completed basic/advanced bloodstain pattern analysis courses at Northwestern University in Chicago, Corning, NY, Lincoln, Nebraska and Des Moines, Iowa. He has attended numerous IABPA Annual Training Conferences including the International IABPA Conference in Middelburg, Zeeland, the Netherlands. He is a graduate of the Iowa Law Enforcement Academy.


Vice President, Region IV Eastern

Anthony Mangione

Anthony became a member of the IABPA in 2002 and is currently serving his second term as Vice President of Region IV (Eastern). He has previously served the IABPA as Sergeant at Arms and, since 2008, has served on the SWGSTAIN Document Review Committee. Anthony currently serves as Co-Chair of the IABPA Certification Research Committee. Anthony has over 16 years of prior military experience, having served on active duty and reserves in the US Army as an RTO, Infantry Scout, Drill Instructor, and Infantry Platoon Sergeant. Anthony served with the 7

th and 2

nd Infantry Divisions and also served on the

Korean DMZ and in Central America. He was assigned to the 78th

Division Special Weapons Committee, then assigned to the US Army Drill Sergeant Academy at Ft. Dix, NJ and served as an Instructor/Course Manager. After completing his tours of duty, Anthony was employed in the private sector in various positions in private security and investigations.

Anthony has 23 years of law enforcement experience. In 1990, Anthony began his law enforcement career as a patrol officer in Hamilton, New Jersey. During his career, Anthony has had an extremely broad experience base from various law enforcement assignments – including patrol, anti-crime unit, fugitive task force, narcotics/vice unit, training unit, criminal investigations bureau and the crime scene unit. He has received thousands of hours in advanced training in criminal investigations and crime scene investigation. Anthony also completed the New York City Police Department’s Homicide Investigator Course.

Anthony’s training and experience in crime scene investigation began in 1993 when he was trained as an evidence technician. He has since been involved in thousands of investigations involving crime scenes of all types. In 2002, Anthony was promoted to Detective and is currently the senior crime scene investigator at the Hamilton Police Division where he designed, developed and implemented the Hamilton Police Division Crime Laboratory and implemented the Digital Information Management System – and most recently, the design and implementation of the Crime Scene Unit’s Mobile Crime Lab. Anthony is a certified instructor and has taught law enforcement and forensic topics across the country. Anthony was involved in the development of the Northeast Crime Scene Institute located in Somerset County, New Jersey – where he currently serves as Chairman of the Education Committee and as a staff instructor. He is also a member of the IAI, the New Jersey Division of the IAI, NJAFS, the New Jersey Police Honor Legion, and the Italian-American Police Society.


Vice President - Region V

European

Peter Lamb

Peter Lamb started his career in 1970 as an assistant with the UK Home Office and did his

professional qualifications part time at the local university and on completion was promoted to Reporting Officer status. He worked on all cases of offences against the person. Peter began studying blood stain patterns in 1973 and enjoyed conducting research with blood. He became a blood stain pattern trainer for the Forensic Science service and helped train many of the experts in the UK and overseas.

Peter was awarded Fellowship of the Society of Biology for his work in Forensic Science and later, also became a Fellow of the Forensic Science Society. He joined the IABPA so that he could meet other experts and learn from them and contribute my knowledge and was delighted to take over from Andre Hendrix as Vice President region V. In 2011 the UK Government closed the Forensic Science Service and Peter became a self-employed consultant.


Vice President - Region VI

Pacific Rim

Sergeant Brett McCance

Sergeant McCance is a Senior Forensic Investigation Officer and Team Leader with the Western Australia Police Forensic Division. Sergeant McCance graduated from the Western Australia Police Academy in 1996 and started his career in the Forensic Division in 2001, which involves the attendance at scenes of both volume and major crime. Sergeant McCance commenced his training as a bloodstain pattern analyst in 2004 and is still active in scene attendance and case work for bloodshed events, being accepted by the Western Australia Supreme Court, District Court and Coroners Court as an expert in the scientific discipline. Sergeant McCance was the Forensic Division discipline manager for bloodstain pattern analysis for two years and has delivered and coordinated internal training courses for the Western Australia Police Forensic Division and national training courses for policing and laboratory jurisdictions within Australia. Sergeant McCance became a member of a national steering committee to standardize the education and training of bloodstain analysts within Australia in 2006. In 2010, Sergeant McCance became a member of SWGSTAIN on the Quality and Assurance sub-committee. Sergeant McCance has also presented at national and international conferences and symposiums on bloodstain pattern analysis and is currently undertaking studies towards a Bachelor of Science in Crime Scene Investigation.


Secretary - Treasurer

Norman Reeves

Norman's initial bloodstain pattern analysis training occurred in 1975 and he has continued to pursue that field of endeavor to this day. Norman is a founding member of the IABPA and he was the first to testify in the area of Bloodstain Pattern Analysis in New Jersey in 1983. Norman was a certified instructor in New Jersey and he has lectured many times regarding bloodstain pattern analysis and he has provided numerous testimonies in the New Jersey Courts. He has also provided instruction of bloodstain pattern analysis in other jurisdictions.

Norman retired in 1991 and began consulting that resulted in examinations of bloodstains in numerous jurisdictions throughout the world and subsequent testimony. Norman was the Editor of the IABPA Newsletter in 1987-1989 and has been Secretary/Treasurer of the IABPA since 1991. He was honored with the IABPA Distinguished Member status in 1996. Norman has hosted four IABPA Training Conferences with the most recent in Tucson, Arizona in 2012.


Sergeant at Arms

Jeffrey Scozzafava

Jeff became a member of the IABPA in 2002 and has attended 9 of the previous 10 Annual Training Conferences. Jeff has given multiple case presentations and has instructed several workshops at IABPA conferences. Jeff has previously served the IABPA as Vice President of Region IV (Eastern) Sergeant at Arms, Chair of the Internet Subcommittee, and member of the SWGSTAIN Document Review Committee.

Jeff has 30 years of law enforcement experience. Beginning in 1983, Jeff served active duty in the US Army as a Military Policeman. After completing his tour of duty, Jeff became a New Jersey State Trooper, and retired from the State Police as a Detective Sergeant, serving over half his career as a crime scene investigator.

Jeff works as a Detective for the Somerset County Prosecutor’s Office, assigned to the Forensic Investigations Unit. He is also a member of the County’s Dive-Rescue Team, Arson Task Force and the Police Shooting Response Team.

Jeff is a certified instructor and has taught forensic topics across the United States and overseas. Jeff has instructed for the U.S. Department of Justice, John Jay College, NY, the IAI, the New Jersey State Police and NJ Division of Criminal Justice. Jeff has testified as an expert witness in Superior and Federal Courts regarding bloodstain pattern analysis, fingerprint identification and crime scene investigation.


Immediate Past President

Todd A. Thorne Todd A. Thorne is currently working in both the law enforcement and private communities. Todd is well versed in Bloodstain Pattern Analysis, Forensic Photography, Evidence Processing Techniques as well as Crime Scene Reconstruction. He is also a Latent Fingerprint Examiner. Todd has a variety of published articles and photographs in these disciplines. Todd has been working in the field of criminalistics for over 25 years and continually offers expert testimony/consultation. He is a certified State of Wisconsin and Illinois Instructor and has been on staff with the Nebraska Institute of Forensic Science. Todd is a sought after speaker and is an adjunct instructor in the area of Forensic Science for several colleges. In addition, he has served on the State of Wisconsin's Domestic Violence/Sexual Assault Evidence Training Team. Todd has been a member of the Federal Government's U.S. Department of Homeland Security, serving with the DMORT V Disaster Response Unit. He operates Todd A. Thorne & Associates Forensic Consultants and Photography Services, LLC, which has exposed him to both national and international cases. Todd instructs throughout the country for The Lynn Peavey Company and has been called upon for technical consultation/research by various entities. He has also served the Wisconsin Association for Identification as President, Chairman of the Board and has chaired numerous committees, The International Association of Bloodstain Pattern Analysts as Region 3 Vice President, Associate Editor and The Kenosha Professional Police Association as the secretary. Todd's hobbies include family activities, church activities, camping and photography. He is married with 5 children.


Historian

Stuart H. James

Stuart H. James of James and Associates Forensic Consultants, Inc. is a graduate of Hobart College where he received a BA degree in Biology and Chemistry in 1962. He received his MT(ASCP) in Medical Technology from St. Mary’s Hospital in Tucson, Arizona in 1963. Graduate courses completed at Elmira College include Homicide Investigation, Bloodstain Pattern Analysis and Forensic Microscopy. He has completed more than 400 hours of continuing education and training in Death Investigation and Bloodstain Pattern Analysis. A former Crime Laboratory supervisor in Binghamton, New York, he has been a private consultant since 1981.

Mr. James has instructed in Forensic Science at the State University of New York and Broome Community College in Binghamton, New York. Additionally, he has taught basic and advanced Bloodstain Pattern Analysis courses throughout the country and internationally. He has been consulted on homicide cases in 47 States and the District of Columbia as well

as in Australia, Canada, Germany, The Netherlands, Puerto Rico, South Korea and the US Virgin Islands and has provided expert testimony in many of these jurisdictions in state, federal and military courts.

Mr. James is a co-author of the text entitled, Interpretation of Bloodstain Evidence at Crime Scenes and has contributed to other forensic texts including Introduction to Forensic Science, Practical Fire and Arson Investigation and the Practical Methodology of Forensic Photography. He is also a co-author of the revised Second Edition of Interpretation of Bloodstain Evidence at Crime Scenes and the Editor of Scientific and Legal Applications of Bloodstain Pattern Interpretation both of which were published in 1998. He is a co-editor with Jon J. Nordby of the text entitled Forensic Science – An Introduction to Scientific and Investigative Techniques first published in 2002 with the third edition published in 2009. He is also a co-author with Paul Kish and T. Paulette Sutton of the text entitled Principles of Bloodstain Pattern Analysis – Theory and Practice published in 2005. Mr. James is a fellow in the American Academy of Forensic Sciences and a distinguished member of the International Association of Bloodstain Pattern Analysts (IABPA) and Historian as well as the current editor of the quarterly Journal of Bloodstain Pattern Analysis.


TECHNICAL PAPER The Development and Construction of a Motorized Blood Droplet Generation Device (BDGD) for Detailed Analysis of Blood Droplet Dynamics Elisabeth Williams

1,2, and Michael Taylor

1

Abstract

This work presents a motorized, mechanical blood droplet generation device (BDGD) capable of generating and projecting reproducible blood droplets at a range of sizes, velocities and directions relevant to a number of crime scene applications, particularly cast-off and impact patterns. The BDGD has facilitated comprehensive, systematic, controlled experimental work including a detailed analysis of the fluid dynamics of blood drops during flight and impact. This level of control and reproducibility are impossible to achieve in experiments using human-wielded weapons. The BDGD is complemented by an LED lighting system, enabling droplet dynamics to be filmed with one or more high speed digital video cameras. It features an automated blood application pump, ensuring a controlled blood volume. The ability to generate and analyse blood drop dynamics in such a controlled manner lends itself to the development of statistical models which can aid in the presentation of objective bloodstain evidence. Introduction

There is currently a dearth of controlled, systematic experimental work on blood droplet behaviour, in the bloodstain pattern analysis (BPA) literature. This means, for example, the science under-pinning the use of predictive models to calculate the impact angle and the area of origin of bloodstains is limited [1]. Blood droplets are generally thought to travel as oscillating spheres, whose oscillations dampen after a time due to viscosity, with the spherical shape ensured by the surface tension properties of the blood [2-4]. Recent studies have utilized high speed video to examine the dynamics of falling droplets with regard to droplet deformation on angled surfaces, the effects of gravitational and drag forces and terminal velocity [5-7]. This level of analysis however, has not yet evolved to analysing upwardly moving droplets, relevant to cast-off and impact patterns. While the effect of gravity and drag can be modelled using equations which incorporate the physical properties of blood and air, a variety of other factors including impact surface characteristics can influence blood drop behaviour at crime scenes and thus systematic experimentation is required.

One of the challenges for research into spatter patterns is generating consistently-sized small droplets at higher velocities than a passive dropping experiment can achieve. To make this possible we have designed and built a blood droplet generation device (BDGD). The device is comprised of a motorized rotating disc, based on the concept of rotary atomisation, to generate uniform droplet sizes. Rotary atomisation is one of many atomization techniques employed in various industrial applications such as spray cooling and ink jet printing [8]. In this process liquid is applied to a rotating disc. During rotation the liquid migrates to the edge of the disc where it forms ligaments or sheets which disintegrate into droplets and detach from the disc’s surface [8]. _________________________________________________________________________ 1Environmental Science and Research Ltd (ESR), Christchurch, New Zealand

2Department of Sport and Exercise Science, University of Auckland, New Zealand


The design of the circular disc BDGD enables blood droplets to be projected at any angle in the plane in which the disc is set. The direction of the device disc can be reversed, so that stains created from upward-propelled droplets can be compared with those from downward and horizontally propelled droplets.

The BDGD was primarily designed to study cast-off droplets. To determine the relevant range of velocities for cast-off, preliminary biomechanical trials were conducted with the assistance of motivated human volunteers swinging various weapons towards (‘forward swing’) and away from (‘back swing’) a blood-soaked target. The weapon with the greatest end-point velocity was the baseball bat which measured up to 15 m/s during back swing and up to 36 m/s during forward swing [9]. A target velocity of 40 m/sec was chosen for the maximum disc tangential velocity.

Droplet size can be controlled to an extent by controlling the volume applied. Droplets and stains can be mapped and graphed relative to a global coordinate system and a high-intensity backlighting system enables fine details of droplet dynamics to be captured with a high speed video camera. Particular attention was given in the design to the health and safety requirements of the laboratory. Prototype Development and Preliminary Experiments

Preliminary droplet generation experiments were conducted using a prototype apparatus comprising of a 200 mm diameter Formica disc with shallow surface grooves, attached to the shaft of a 0.09 kW motor wired to a variable speed drive (VSD). The tangential velocity of the disc perimeter was set to 10 m/s and blood applied to the surface via a syringe. The droplets produced were smaller (0.2-0.4 mm in diameter) than those expected in cast-off, which was attributed to the relatively small radius of the disc and correspondingly large centripetal forces generated by the disc. A much larger disc diameter was therefore required to obtain appropriate sized drops to model cast-off. Design and Construction of Device

The final design, (Figure 1) included the following features: A 6.0 mm thick, 600 mm diameter aluminum disc with stainless steel hub A 0.3 kW motor with a drive shaft and pulley system A variable speed drive (VSD) unit, controlled by a 10 turn potentiometer and on/off

switch to control the motor A comprehensive framing system and weighted support base A medical pump to apply blood to the disc A safety cage A high intensity LED array backlighting system A 2.4 x 1.2 m frosted Perspex® diffuser screen, which doubled as a global coordinate

system (GCS) grid

Disc Size and Features

The diameter of the disc was chosen to be 600 mm, which represented a realistic size for adequate control for tangential velocities up to 40 m/sec. The disc was cut from a sheet of 6 mm aluminium which provided a lightweight but strong structure capable of spinning without flexing or oscillating. The disc had twelve evenly spaced, 170 mm long, 1.0 x 1.0 mm radial grooves milled into it from the disc perimeter to the centre. These were designed to encourage the fluid to pool, rather than be randomly distributed around the disc as it rotated. Aluminium radial veins were attached to the left edge of each groove (Figure 2) to increase the volume of blood being propelled from the disc at each point on its circumference and thereby produce larger droplets.


Frame and Base of Device

The circumference of the 600 mm disc is 1885 mm, so the angular velocity required to achieve a tangential velocity of 40 m/s, is 1273 revolutions per minute. Considering the mass of the disc and the torque generated by these relatively high speeds, a comprehensive framing system was constructed and the entire apparatus bolted to a solid support base to eliminate any vibration and prevent any lateral movement. An adjustable work platform, built to withstand heavy loads in the building industry, was used as the base (Figure 3). A 1.5 x 0.8 m, 20 mm Medium Density Fibre Board (MDF®)

was attached to the platform with

12 screws. Prior to mounting, 15.0 mm nuts were counter-sunk into the board, to bolt the machine frame to the MDF (Figure 3).

The frame was designed for maximum stability and to accommodate the motor and pulley system. A platform to support the motor was attached to the rear of the frame and laterally facing grooves were bored into the platform so the motor position could be adjusted to tension the drive belt (Figure 4). Multistrut® construction framing was chosen to build the frame because of its strength and versatility. Multistrut® can be pieced together using bolts and spring nuts; the positions of which can be adjusted if required. Stainless steel angle brackets were used to hold the frame together once the fixed positions were calculated.

Figure 1: Photograph showing the final design of the machine. Dimensions inset: A: height of diffuser screen = 2400

mm. B: width of diffuser screen = 1200 mm. C: Diameter of aluminum disc = 600 mm.

A

B

C


Figure 2: The surface of the straight-edged disc with radial grooves and veins.

Figure 3: The work platform and MDF board, with the Multistrut® frame bolted in place.


Pulley System, Drive Shaft, Motor and Hub

The direct drive arrangement between the motor and the disc used in the prototype was inadequate for a device of larger dimensions. A larger motor was necessary for the fine velocity control required and a pulley system with a fan belt and drive shaft was also necessary for the speed and stability required. The motor was wired up to a variable speed drive, which in turn was connected to a 10-turn potentiometer and an on / off switch, so the speed of the motor could be controlled in fine increments. The appropriate pulley sizes and drive shaft diameter were calculated to achieve the required maximum tangential velocity of 40 m/s with increments of 0.1 m/s. A 26-5M-15 pulley was fitted to the shaft of the motor and a 60-5M-15 pulley was attached to a 30 mm diameter, 50 mm long drive shaft. The pulleys and drive shaft were stainless steel. Two 30 mm pillow block bearings were bolted to the angle brackets at the top centre of the frame, one at the motor end and one at the disc end and the shaft threaded through (Figure 4). The length of the belt to drive the pulleys was measured once these items were in place, the belt attached and the position of the motor adjusted laterally to tighten the belt.

A two-piece circular stainless steel hub was machined to securely attach the disc to the drive shaft and to prevent any torsion or oscillation of the disc. A bolt-hole matching that on the disc (Figure 3) was drilled into the 20.0 mm thick, 255.0 mm diameter outer portion of the hub and planed to sit flush with the rear surface of the disc (Figure 4). Half of the 40 mm thick inner portion was bolted in a similar fashion to the outer portion, with the innermost 20 mm machined to a 60 mm diameter, with three grub screws securing it to the drive shaft (Figure 4).

Figure 4: Multistrut® frame, with 0.3 kW motor, two pulleys and belt drive (left). Two pillow boxes hold the 30 mm shaft, which attaches to the boss on the rear surface of the disc (right).

Velocity Control

The 0.3 kW, 3-phase, 4 pole motor was wired in delta configuration (240 V, AC, 3 phase)

and connected to a SEW Eurodrive Movitrac® variable speed drive (VSD) controller (Figure 5). The VSD controller was wired to a 10 turn potentiometer, via a 1.5 m cable, allowing the operator to stand away from the machine. The potentiometer was mounted in a plastic box with a rotary dial allowing fine control over the velocity and an on/off switch (Figure 6). The


VSD had a digital display in Hz, so a calibration table was written correlating frequency with the tangential speed of the disc perimeter. The VSD settings could be changed so that the rotational direction of the disc could be reversed; this facilitated the generation of upward and downward moving droplets. Velocity could be controlled to 0.1 m/s.

Figure 5: The VSD, cable and potentiometer with rotary dial and on/off switch.

Blood Application Pump

A KNF Neuberger® micro-diaphragm pump was used to apply blood to the disc in controlled amounts. The flow rate of the pump was 3.8 ml/sec and it was approximately 150 x 50 x 50 mm in size (Figure 6a). The pump was wired up to a rotary switch (Figure 6b), with eight time settings; 0.25 sec to 2 sec in 0.25 sec increments and an activation button (Figure 6a).

Figure 6a: KNF Neuberger® pump, rotary switch dial and activation button.

Figure 6b: KNF Neuberger® pump and circuit board with rotary switch.


At the press of the button, the pump activates for the amount of time set by the rotary switch; 0.95 ml in 0.25 sec, 1.9 ml in 0.5 sec, up to 7.6 ml in 2 sec. The pump was mounted onto the device in an aluminum box, screwed to the frame of the safety cage (Figure 10), at the right side of the disc (Figure 7b).

The fluid, which is usually pig blood, was placed on a heating plate behind the disc (Figure 7a), with the temperature of the blood set to whatever value was required for any given experiment. A 5 mm plastic tube, insulated with Centurylon® pipe insulation, ran from the blood source to the pump, where a second tube ran from the pump to the disc, held in place by a bracket (Figure 7b). The pipe insulation ensured that the blood temperature remained constant from the beaker to the disc. The pump was ‘bled’ (blood was pumped through the tube into a waste beaker for 4 seconds) immediately prior to each test to ensure that any effects of blood sitting in the tube for a time; such as a temperature decrease, settling of cells or coagulation, were eliminated. A small plastic hose fitting was placed in the end of the tube facing the disc, to control the direction of expelled blood.

Figure 7a: Blood in a beaker on an element at Figure 7b: The position of the insulated application the rear of the device with an insulated 5 mm hose and pump for upward-moving trials: 20 mm tube running from the beaker to the pump. from the perimeter of the disc, 55 degrees from the horizontal, 15 mm from the surface of the disc and the pump (far right). Diffuser Screen and Global/ Local Coordinate Systems

A diffuser, 2400 mm high and 1200 mm wide, was securely positioned 80 mm behind the front surface of the disc, in the same plane as the disc. The screen was comprised of 6 mm thick frosted Perspex®.

The diffuser screen served four functions; to diffuse the backlighting to create an even level of illumination, to provide a surface for a global coordinate system (GCS) grid to be marked on, to provide a surface to attach impact targets and to provide additional stability to the machine.

The GCS was designed so that the positions of each droplet and resulting bloodstain could be correctly plotted relative to each other and to the position of the disc. The grid coordinates 0,0 in the x and y axes were located at the bottom left corner of the diffuser screen, with the x coordinates increasing to the right and the y coordinates increasing in an upward direction. The centre of the disc was located at x,y coordinates 1100, 990 mm. The flight paths of blood droplets propelled from the disc were plotted according to their GCS coordinates. The device can propel blood drops onto any surface to create test bloodstains. Initial tests utilized Foamcore® strips cut in 2000 mm and 1200 mm lengths, 150 mm wide,


marked with the GCS coordinates and attached to the diffuser screen at 90 degrees (Figure 9).

The device and coordinate system were set up for droplet flight to be filmed with a high speed video camera, positioned perpendicular to the diffuser screen. Image dimensions are measured in pixels so a calibration scale, called a local coordinate system (LCS), was constructed in order to plot droplet position relative to the GCS. A transparent Perspex® box with a millimetre grid was placed in the same plane as the disc in front of the diffuser screen and the camera focused in this plane (Figure 9).

Figure 8: The Perspex® diffuser screen with the global coordinate system (GCS) grid; in 100 mm

squares.


Figure 9: The local coordinate system (LCS) calibration grid being held against the surface of the diffuser

screen.

Safety Features

For safe practice while using the device, several features were added to the design. A safety cage around the disc prevents any projectile accidently released from the rotating disc to be flung toward any personnel or equipment. The cage also catches any blood being released from the edge of the disc, preventing lab contamination and providing stability for the diffuser screen. Lengths of stainless steel slotted angle iron were cut to appropriate lengths and welded in the configuration seen in Figure 11 and bolted to the MDF board. Clear Perspex® windows were cut to size to form a front cover, left side cover, top and bottom as labeled in Figure 10. In addition to the cage, the belt drive also required a cover to minimise the risk of injury from fast moving, rotating parts. An aluminum sheet was screwed to a wooden semi-circular plate and fastened over the belt and pulleys and clear Perspex® sheets were fastened to the cover at right angles, preventing any contact with the belt while the device is in use (Figure 11).


Figure 10: Safety cage surrounding the disc, attached to the MDF board. A: Perspex front cover, B: right side cover, C: bottom cover, D: Top cover with slit for diffuser screen.

Figure 11: The belt drive cover with the clear Perspex® walls.


Backlighting System

A high intensity backlighting system was required for the high speed camera to capture the flight dynamics of small blood droplets travelling at high velocities at a sufficiently high shutter speed to prevent motion blur and a small enough aperture for sufficient depth of field. A four LED array system was assembled for this purpose and will be detailed in a separate publication. An adjustable frame to hold the system was constructed from Multistrut®, which enabled the positions of the LED arrays to be moved according to the area being filmed. Figure 12a provides an illustration of the position of the backlighting frame relative to the diffuser screen and the proximity of the LED arrays to each other; a configuration which was shown to provide the most even illumination at the right intensity to film the blood droplets being propelled from the disc (Figure 12b).

Figure 12a: LED array backlighting system on the

adjustable Multistrut® frame, bolted to the MDF

board.

Figure 12b: The illumination provided by the

backlighting system.

Performance Experiments

Experiments were conducted to determine whether the droplets generated by the device were in the size and velocity ranges of those generated by human-wielded assault weapons (Figure 13). In these initial validation experiments, the tangential velocity of the disc was set to each of the four different velocities in Table 1. The volume of blood applied to the disc was initially 0.98 ml and this was increased if it was found that the blood droplets were smaller than those generated by the human-wielded weapons, until the volume made no difference to the droplet size.


Results

Disc Velocity (m/s) Blood Volume (ml) Average Droplet

Diameter (mm) 6 0.98 0.9 10 0.98 0.6 20 1.9 0.26 30 2.85 0.18

Table 1 showing the range of droplet sizes for each velocity and blood volume.

Figure 14 shows five consecutive images of droplets being propelled at 6 m/s, with 0.98 ml

of blood applied to the disc. It was observed that as the disc rotated, blood travelled to the disc perimeter and formed a ligament as it travels away from the disc. The ligament started to break up when surface tension forces were no longer sufficient to provide the necessary centripetal force to keep the blood on the disc. At this point individual droplets continued to travel in the direction they were travelling at the instant of release from the ligament; on a flight path tangential to the perimeter of the disc. Figure 15, an overlay of the images in Figure 14, shows that initially this is a straight line trajectory; however it is assumed that this trajectory will start to curve due to the forces of air resistance and gravity some time later. During ligament breakup very small droplets can be observed between the larger droplets in figures 15 and 16, while the average size of the larger droplets is similar; a standard deviation of 0.16 was calculated for 200 droplets released at 6 m/s, recorded within 200 mm of the disc perimeter.

Figure 13: Overlaid images of a kitchen knife being swung forcefully backwards by a human volunteer, after being dipped in pig blood. Overlaid graphics illustrate the blood droplet trajectories.


Figure 16 provides a visual comparison of the droplet sizes summarized in Table 1, projected at disc tangential velocities of 6, 10, 20 and 30 m/s with approximately the same global coordinates. It is evident from these results that the device generates droplets smaller than a human wielded baseball bat at 20 and 30 m/s. However it is unlikely to see shorter weapons with tangential velocities in this range in practice, so this remains an acknowledged limitation of the device.

Figure 14: Five still images taken every 0.000926 sec, of blood being propelled off the disc at 6 m/s, filmed at 5400 frames per second at a shutter speed of 1/178000th of a second.


Figure 15: The five still images from Figure 14 overlaid, with inserted graphics illustrating the flight path of each droplet, which in the initial flight phase, is tangential to the perimeter of the disc.

Figure 16: Still photographs of in-flight droplets generated by the device at 6, 10, 20 and 30 m/s.


Conclusions

The BDGD has proved to be capable of generating large numbers of reproducible droplets in any planar direction, within the size and velocity ranges of cast-off from common human-wielded assault weapons relevant to blunt and sharp force trauma, with the exception of a baseball bat being swung at greater than 20 m/s.

In controlled laboratory conditions, each independent variable in the system can be defined, set at a predetermined value, and large numbers of droplets generated, stains created, and results observed. The experimenter can then change one independent variable in that system, keeping all others constant, test again under the new conditions and observe any changes in the outcome variables and the frequency of those changes under the new conditions. An example would be to compare the number of spines and scallops observed in stains created at a given location under condition A, then increasing the tangential velocity of the disc by 3 m/s, and repeating the experiment. The device can generate a sufficient number of results to quantitatively assess the effect of the manipulated independent variable (e.g. initial velocity) on the dependent variables such as measurable stain characteristics. This approach enables, for example, the systematic assessment of the relationship between the trajectory of a constantly accelerating assault weapon swung in an arc, and the resulting cast-off pattern.

Utilizing the backlighting system and global coordinate system, the device can be used as a vehicle to study and understand parabolic blood droplet trajectories and the limitations of the straight line trajectory calculation methods. Blood droplet trajectories can be mapped and plotted and databases of the dynamics of different sized droplets can be developed over time.

In case specific experimentation, the device can be used in hypothesis testing in a systematic fashion, incorporating factors such as the effect of the impact surface on stain formation, and subsequent impact angle calculation.

The enhanced back-lighting system provides the means to analyse the oscillation amplitude of individual droplets, and the time to dampening for droplets created under a range of conditions; velocities, drop sizes and viscosity values, so that the effect of oscillation on stain formation and the accuracy of the subsequent impact angle calculation can be evaluated experimentally.

While a simple concept and a relatively straightforward design, the BDGD provides an effective vehicle to improve the scientific rigour behind bloodstain impact angle reconstruction and can quantitatively test some of the fundamental principles of bloodstain pattern analysis.

Acknowledgements

This project would not have been possible without the invaluable contribution from the following people and organisations: Dan Rahn Memorial Research Grant Committee, International Association of Bloodstain Pattern Analysts (IABPA). Dr. Sharon Walt, Dr. Ir. Ron McDowall, Ian Williams; Agcon Engineering Ltd, Drury, Peter O’Gara; O’Gara Engineering, Graeme Harris, Scott Aimes, Jim Maclean, Julian Phillips, Dave Read, Ken Brown, Dr Mark Jermy; Department of Mechanical Engineering, University of Canterbury, Gary Donaldson; Bretmar Transmission Company Ltd, Papakura, Multistrut

(R)

Ltd, NZ. FreshPork NZ Ltd, Bay City Abattoir, Timaru. The principal author (E.W) acknowledges receipt of a Dan Rahn Memorial research grant

which supported this study. The authors with to thank Dr Rachel Fleming and Gary Gillespie for reviewing this manuscript.


References 1. NAS, Strengthening Forensic Science in the United States: A Path Forward. The National Academies

Press, 2009. 2009.

2. Raymond, M.A., E.R. Smith, and J. Liesegang, The physical properties of blood - forensic

considerations. Science and Justice - Journal of the Forensic Science Society, 1996. 36(3): p. 153-160.

3. Bevel, T.a.G., Ross, Bloodstain Pattern Analysis with an Introduction to Crime Scene Reconstruction.

CRC Series in practical aspects of criminal and forensic investigations 1002 Boca Ralton: CRC Press

LLC, 2006.

4. Raymond, M.A., E.R. Smith, and J. Liesegang, Oscillating blood droplets - implications for crime

scene reconstruction. Science and Justice - Journal of the Forensic Science Society, 1996. 36(3): p.

161-171.

5. Hulse-Smith, L., N.Z. Mehdizadeh, and S. Chandra, Deducing drop size and impact velocity from

circular bloodstains. Journal of Forensic Sciences, 2005. 50(1): p. 54-63.

6. Knock, C. and M. Davison, Predicting the position of the source of blood stains for angled impacts.

Journal of Forensic Sciences, 2007. 52(5): p. 1044-1049.

7. Hulse-Smith, L. and M. Illes, A blind trial evaluation of a crime scene methodology for deducing

impact velocity and droplet size from circular bloodstains. Journal of Forensic Sciences, 2007. 52(1):

p. 65-69.

8. Liu, H., Science and Engineering of Droplets: Fundementals and Applications. 2000: William Andrew

Publishing. 527.

9. SWGSTAIN, S.W.G.o.B.P.A., Recommended Terminology. Forensic Science Communications, 2009.

11(2).

10. Bevel, T., Gardner, R.M.. Bloodstain Pattern Analysis with an Introduction to Crime Scene

Reconstruction. 3rd ed. 2008, Boca Raton, FL: CRC Press.

11. MacDonell, H.L., Bloodstain Patterns. 2nd ed. 2005, Corning, NY: Laboratory of Forensic Sciences.

12. Williams, E., The Biomechanics of Blunt Force Trauma. Masters Thesis in Forensic Science,

University of Auckland, 2008, 2008.

13. Wonder, A., Blood Dynamics. Academic Press, 2008.

14. James, S.H., Kish, P.E., Sutton, T.P., Principles of Bloodstain Pattern Analysis: Theory and Practice.

2005, Boca Raton, FL: CRC Press; Taylor and Francis Group.

15. Fischer, W.C., Utilizing Bloodstains in Accident Reconstruction, in Scientific and Legal Applications

of Bloodstain Pattern Interpretation, S.H. James, Editor. 1998, CRC Press: Boca Raton, FL.

16. Serway, R.A.a.J., J.W, Physics for Scientists and Engineers. 8th Ed. Pacific Grove, CA. Brooks Cole,

2009.


Recent BPA Related Articles in the Scientific Literature

Praska, N., and Langenburg, G., Reactions of Latent Prints Exposed to Blood, Forensic Science International, Vol. 224, Issue 1, pp. 51-58, January 2013. Moret, S., Bécue, A. and Champod, C., Cadmium-free Dots in Aqueous Solution: Potential for Fingermark Decection, Synthesis and an Application to the Detection of Fingermarks in Blood on Non-Porous Surfaces, Forensic Science International, Vol. 224, Issue 1, pp. 101-110, January 2013. Sundarrajan, R. and Pathak, R., Investigating the Force Relative to Bloodstain Size and Pattern, Indian Journal of Forensic Medicine and Toxicology, Vol. 6., No. 2, July-December, 2012.

Feia, A. and Novroski, The Evaluation of Possible False Positives with Detergents when Performing Amylase Serological Testing on Clothing, J. Forensic Sci, January 2013, Vol 58, No. S1.

Seashols, S. J., Cross, H. D., Shrader, D. L., and Rief, A., A Comparison of Chemical Enhancements for the Detection of Latent Blood, J. Forensic Sci., January 2013, Vol. 58, No. 1.

DeCastro, T., Nickson, T., Carr, Debra and Knock, C. Interpreting the Formation of Bloodstains on Selected Apparel Fabrics, International Journal of Legal Medicine, Vol.27, Issue 1, pp. 251-258.

Farrugia, K.J., Bandey, H., Savage, K., and NicDaéid, N., Chemical Enhancement of Footwear Impressions in Blood on Fabric – Part 3: Amino Acid Staining


Organizational Notices

Moving Soon?

All changes of mailing address need to be supplied to our Secretary Norman Reeves. Each quarter

Norman forwards completed address labels for those who are members. Do not send change of address information to the Journal Editor. E-mail your new address to Norman Reeves at:

[email protected]

Norman Reeves

I.A.B.P.A.

12139 E. Makohoh Trail

Tucson, Arizona 85749-8179

Fax: 520-760-5590

Membership Applications / Request for Promotion

Applications for membership as well as for promotion are available on the IABPA website:

IABPA Website: http://www.iabpa.org

The fees for application of membership and yearly dues are $40.00 US each. If you have not received a dues invoice for 2013 please contact Norman Reeves. Apparently, non US credit cards are charging a fee above and beyond the $ 40.00 membership/application fee. Your credit card is charged only $40.00 US by the IABPA. Any additional fees are imposed by the credit card companies.

IABPA now accepts the following credit cards:

Discover MasterCard

American Express Visa


http://www.iabpa.org/


Training Opportunities

April 8-12, 2013

Advanced Bloodstain Pattern Analysis Course

Loci Forensics B.V.

Flierveld 59

2151 LE Nieuw-Vennep

The Netherlands

Instructors: Martin Eversdijk and René Gelderman

Fax: +31(0)20-8907749

E-mail: [email protected]

April 22-26 2013

Basic Bloodstain Pattern Analysis Course

(English)

Blutspureninstitut

Obergasse 20

61250 Usingen

Germany

Instructor: Dr. Silke Brodbeck, MD

Tel: +49-170-84 84 248

Fax: +49-6081-14879

April 29-May 3, 2013

Math and Physics for Bloodstain Pattern Analysis

Ontario Police College

10716 Hacienda Rd. Box 1190

Aylmer, Ontario, Canada

N5H 2T2

Instructor: Brian Allen

Tel: 519-773-4258

Fax: 519-773-5762





May 13-17, 2013

Visualization of Latent Bloodstain Course

Loci Forensics B.V.

Flierveld 59


The Netherlands


Fax: +31(0)20-8907749


June 3-7, 2013

Basic Bloodstain Pattern Analysis Course

(German)

Blutspureninstitut

Obergasse 20

61250 Usingen

Germany


Tel: +49-170-84 84 248

Fax: +49-6081-14879

June 17-21, 2013

The Fabrics of Bloodstain Pattern Course

Loci Forensics B.V.

Flierveld 59


The Netherlands


Fax: +31(0)20-8907749


September 9-13, 2013


Ontario Police College

10716 Hacienda Rd. Box 1190

Aylmer, Ontario, Canada

N5H 2T2

Instructor: Brian Allen

Tel: 519-773-4258

Fax: 519-773-5762







Basic Bloodstain Analysis Course

Loci Forensics B.V.

Flierveld 59


The Netherlands


Fax: +31(0)20-8907749




(German)

Blutspureninstitut

Obergasse 20

61250 Usingen

Germany


Tel: +49-170-84 84 248

Fax: +49-6081-14879

October 7-11, 2013

Fluid Dynamics of Bloodstain Course

Loci Forensics B.V.

Flierveld 59


The Netherlands

Instructors: Dr. Michael Taylor and Dr. Mark Jermy

Fax: +31(0)20-8907749


October 14-18, 2013


(English)

Blutspureninstitut

Obergasse 20

61250 Usingen

Germany


Tel: +49-170-84 84 248

Fax: +49-6081-14879




November 18-22, 2013

Advanced Bloodstain Analysis Course

Loci Forensics B.V.

Flierveld 59


The Netherlands


Fax: +31(0)20-8907749


December 9-13, 2013

Visualization of Latent Bloodstain Course

Loci Forensics B.V.

Flierveld 59


The Netherlands


Fax: +31(0)20-8907749


December 9-13, 2013

Basic Bloodstain Pattern Analysis Workshop

Specialized Training Unit

Miami-Dade Public Safety Training Unit

Doral, Florida

Contact: Toby L. Wolson, M.S., F-ABC

Miami-Dade Police Department

Forensic Services Bureau

9105 N.W. 25th

Street

Doral, Florida 33172

Voice: 305-471-3041

Fax: 305-471-2052


Articles and training announcements for the June 2013 issue of the Journal of Bloodstain Pattern Analysis must be received before May 30

th, 2013




Editor’s Corner

Congratulations to Pat Laturnus on his election as the 15th

President of the IABPA and to the elected Board members for 2013. They are featured in this issue of the Journal with photographs and short bios.

Our publication is now entering its third year as the Journal of Bloodstain Pattern Analysis and the submission of research articles and case studies for peer review and publication has been slow. You can easily see by the section “Recent BPA Articles in the Scientific Literature” that I have been compiling for a long time. that authors are submitting articles to other Journals rather than ours. Unfortunately, many of the BPA analysts in our organization do not have direct access to these Journals and therefore do not have the opportunity to read these articles.

I do appreciate the efforts of those of you who have submitted articles including Elisabeth Williams and Michael Taylor for their contributions including a fine research article that is published in this issue.

I have suggested in the past that presentations given at our Annual Training Conferences be given priority consideration for publication. I would like some input from the membership on ideas to generate more interest in submitting articles and how they can be implemented to further expand the quality of our Journal.

Stuart H. James Editor [email protected]



Publication Committee

Associate Editors

Barton P. Epstein Carolyn Gannett

Paul E. Kish Daniel Mabel

Jeremy Morris Jon J. Nordby

Joe Slemko T. Paulette Sutton Todd A. Thorne

Past Editors of the IABPA News/Journal of Bloodstain Pattern

Analysis

Anita Y. Wonder 1984-1985 Norman Reeves 1984-1989 David Rimer 1990-1996 Toby L. Wolson 1997-2000 Paul E. Kish 2001-2003 Stuart H. James 2004-present

Past Presidents of the IABPA

V. Thomas Bevel 1983-1984 Charles Edel 1985-1987 Warren R. Darby 1988 Rod D. Englert 1989-1990 Edward Podworny 1991-1992 Tom J. Griffin 1993-1994 Toby L. Wolson, M.S. 1995-1996 Daniel V. Christman 1997-1998 Phyllis T. Rollan 1999-2000 Daniel Rahn 2001-2002 Bill Basso 2002-2006 LeeAnn Singley 2007-2008 Iris Dalley 2009-2010

The Journal of Bloodstain Pattern Analysis published quarterly in March, June, September, and December. 2013. The International Association of Bloodstain Pattern Analysts. All rights are reserved. Reproduction in whole or in part without written permission is prohibited.

Table of Contents publications...Anthony currently serves as Co-Chair of the IABPA Certification...

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Transcript of Table of Contents publications...Anthony currently serves as Co-Chair of the IABPA Certification...