FORENSIC SCIENCE

PHYSICAL EVIDENCE“EVERY CONTACT LEAVES ITS TRACE”

“Wherever he steps, whatever he touches, whatever he leaves, even unconsciously, will serve as silent witness against him. Not even his fingerprints or his footprints, but his hair, the fibers from his clothes, the glass he breaks, the tool mark he leaves, the paint he scratches, the blood or semen he deposits or collects-- all of these bear mute witness against him. This is evidence that does not forget. It is not confused by the excitement of the moment. It is not absent because human witnesses are. It is factual evidence. Physical evidence cannot be wrong; it cannot perjure itself. It cannot be wholly absent; only its interpretation can err. Only human failure to find it, study and understand it, can diminish its value.”

• “Forensic” comes from the Latin word “forensis” meaning forum

• The individual with the best argumentation and delivery would determine the outcome of the case. In other words, the person with the best forensic skills would win.

History of Forensics

• 700’s Chinese used fingerprints to establish identity on clay tablets

• 1248 Chinese: 1st recorded medical knowledge on solving a crime. Distinguished between drowning and strangulation

• 1784 John Toms of Lancaster, England: convicted murder based on wad of paper in pistol matching half in his pocket. First use of physical evidence

• 1810 Surete of Paris: First detective force

• 1905 FBI formed via Theodore Roosevelt

• 1910 Edmond Locard:– Locard Exchange Principle: always a transfer

of evidence when contact is made between person or place. Ex. Dog hair

• 1923 Frye v. United States: A scientific principle must gain “general acceptance” among scientific community

• 1977 AFIS: Automated Fingerprint Identification System

• 1986 DNA evidence

• 1993 Daubert et al v. Merrell Dow: Three key provisions– Scientific knowledge– Assist the trier of fact (jury or judge)– Judge is “gate keeper”

• 1998 NIDIS: FBI DNA database

Criminalist to Forensic Science Specialists

• Criminalist-Crime-scene investigator

-Latent print examiner

-Firearms examiner

-Tool mark examiner

-Document examiner

-Trace Evidence examiner

• Forensic Science Specialists

-Pathologist

-Anthropologist

-Odontologist

-Entomologist

-Physiatrist

-Serologist

-Toxicologist

-Botanist

Role of the Criminalist/Forensic Scientist

• Render impartial findings based on scientific evidence

• Act as an expert witness ( can give opinion)

• Findings may serve to…– Establish crime has been committed– Establish and link elements of crime– Confirm and refute eyewitness testimony– Establish a time frame

– Induce a confession– Include/exclude suspects– Give information on modus operandi (mo)

• MO: Learned behavior, can change, what criminal did to commit the crime (location, point of entry, tools, time of day, alibi)

• Signature: Does not change, expresses killers personality, pose victim in religious manner

VANPAC Bomber• Dec 16 1989 – Federal Judge Robert Vance in

Alabama killed by box in the mail• Dec 18 – Attorney Robert Robinson in Georgia

died from a second package bomb• Dec 18 – 3rd bomb found during routine

screening in an Atlanta courthouse• Dec 18 – 4th bomb was delivered to a female

employee of the NAACP legal counsel in Florida; she went to run errands, her car broke down, she forgot about the package in her back seat of car. Heard about bombing on the news, called bomb squad next day.

VANPAC Bomber cont.• All 4 bombs were constructed the same

– Black enamel painted box

• FBI agent talked with an ATF agent who thought it sounded like a 1972 bomb

• Found bomber of 1972 case, Walter Leroy Moody had recently been released from prison

• Further investigation found evidence to convict for new bombings

Son of Sam Signature• I am deeply hurt by your calling me a wemon

hater. I am not. But I am a monster. I am the "Son of Sam." I am a little "brat". When father Sam gets drunk he gets mean. He beats his family. Sometimes he ties me up to the back of the house. Other times he locks me in the garage. Sam loves to drink blood. "Go out and kill" commands father Sam. Behind our house some rest. Mostly young — raped and slaughtered — their blood drained — just bones now….

Crime Lab Services

• Federal– FBI: to provide impartial services for all federal

agencies in criminal and civil matters as well as state and local

– DEA: Drug Enforcement Agency– ATF: Alcohol Tobacco Firearms– U.S. Postal Inspection Service

• State– Crime Labs (State Highway Patrol)

• Local– St. Louis City and County Crime Lab

Copy the text below in the space above the lines.Do NOT write on the lines.

I have your daughter. Do what you are toldand no one will get hurt. Put 100,000 dollarsworth of 20’s in a suitcase and place it inlocker number C8160 at the bus depot. Iwill get back in touch with you as to thewhereabouts of your daughter.Your loyal fan.

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You didn’t follow directions! Your daughter’s life is in real danger! You have one more chance to get this right. Now I want 200,000 dollars worth of 20’s in a suitcase. Get it ready and wait for further instructions.

Still your loyal fan