Intro to Forensic Science

What is Forensic Science?• The study and application of science to matters of law• “Forensis” meaning forum

• Public place where, in Roman times, senators and others debated and held judicial proceedings

Criminalistics vs. Criminology• Criminalistics – the scientific

examination of physical evidence for legal purposes

• Criminology – includes the psychological angle, studying the crime scene for motive, traits, and behavior that will help too interpret the evidence

The Crime Lab• Physical Science Unit

• Chemistry• Physics• Geology

• Biology Unit• Firearms Unit• Document Examination Unit• Photography• Toxicology and Drug Analysis Unit• Fingerprint Unit

Physical Science Unit• Examines things like:

• Soil• Glass• Paint• Blood spatter patterns• Fibers

• Uses the sciences of:• Chemistry• Physics• Geology

Biology Unit• Examines things like:

• Body fluids• DNA• Blood factors• Hair• Plant matter

• Uses the sciences of:• Biology• Biochemistry• Microbiology

Firearms Unit• Examines things like:

• Bullets and shell casings• Weapons• Tool marks

Document Analysis Unit• Examines things like:

• Handwriting• Typewriting• Word processing and computer applications• Paper• Ink

Major Crime Labs• May also have units for:

• Arson analysis• Polygraphs• Evidence collection• Forensic Odontology• Forensic Entomology• Digital Forensics

History of Forensic Science• Historical Timeline Activity

• Get assigned topic• Research your topic tonight. The question is what was your person/thing’s

major contribution to, or role in, the development of forensic science?• Tomorrow – team up and create mini posters to complete the timeline

NOTE: Bring markers/colored pencils tomorrow!

Criminal Justice and the Law• US Constitution – Supreme law of the land; trumps all other laws• Statutory – written (”codified”) law enacted by a governmental body

empowered to make laws (ie. Congress); based on Constitution• Common Law or Case Law – law made by judges applying the statutory

and constitutional law to the facts of each case• Civil Law – involves relationships between people involving things like

property and contracts• Criminal Law – deals with the regulation and enforcement of rights• Equity Law – deals with remedial or preventive measures like restraining

orders and injunctions• Administrative Law – rules established by agencies such as the IRS

The Bill of Rights – Gives individuals the right...

• To be presumed innocent unless proven guilty

• Not to be searched unreasonably• Not to be arrested without probable cause• Against unreasonable seizure of personal

property• Against self-incrimination• To fair questioning by the police• To protection from physical harm

throughout the judicial process• To an attorney• To trial by jury• To know any charges against oneself

• To cross-examine prosecution witnesses• To speak and present witnesses• Not to be tried again for the same crime• Against cruel and unusual punishment• To due process• To a speedy trial• Against excessive bail• Against excessesive fines• To be treated the same as others,

regardless of race, gender, religious preference, country of origin, and other personal attributes

Jurisdiction• Federal• State• Local• Criminal Court• Civil Court

Judicial Process• Crime is committed• Evidence is collected and a suspect may be identified• Investigation is conducted and given to District Attorney• If there is enough evidence for probable cause, an arrest warrant is

issued• Probable cause – a reasonable person would look at the evidence and

conclude that a crime ahs been committed and that the defendant did it

• Suspect arrested, fingerprinted, photographed and read Miranda rights

Miranda v. Arizona In 1963, Ernesto Miranda, a 23 year old mentally disturbed man, was

accused of kidnapping and raping an 18-year-old woman in Phoenix, Arizona. He was brought in for questioning, and confessed to the crime. He was not told that he did not have to speak or that he could have a lawyer present. At trial, Miranda's lawyer tried to get the confession thrown out, but the motion was denied. The case went to the Supreme Court in 1966. The Court ruled that the statements made to the police could not be used as evidence, since Mr. Miranda had not been advised of his rights.

Process Continued• For felonies, a grand jury issues an indictment

• Indictment – formal charges

• Defendant is arraigned• Arraignment – the first act in a criminal proceeding when a defendant is brought

before a judge to hear charges and enter a plea

• Discovery takes place• Discovery – the results of the State’s investigation are given to the defendant in order

to prepare for trial

• Trial• Sentencing (if appropriate)• Appeals

Standard Miranda WarningYou have the right to remain silent. Anything you say can and will be used against you in a court of law. You have the right to speak to an attorney, and to have an attorney present during questioning. If you cannot afford an attorney, one will be appointed for you at the government’s expense.

Guilt• District Attorney tries to prove that the defendant had the

• Means – the ability to commit the crime• Motive – a reason to commit the crime (not required to convict)• Opportunity – the person can be placed at the scene of the crime

Types of Crimes• Infraction

• Minor matter like a noise violation

• Misdemeanor• In NC, a crime for which the max penalty is 1 year in jail• 3 classes of misdemeanors:

• Class 3 – Possession of <1/2 oz marijuana• Class 2 – trespassing• Class 1 – DWI• Class A1 – Assault on a Female

• Felonies

Felonies• Levels from Class A (ie. premeditated murder) to Class I – Possession

of >1/2 oz marijuana• Sentences from 6 months to the death penalty• Forensics involved

Federal Rules of Evidence• In order for evidence to be admissible in court, it must be:

• Probative – actually prove a material fact in the case• Material – address an issue that is relevant to the particular crime

Admissibility of EvidenceFrye v. United States (1923)

• Admissibility is determined by• Generally accepted by the relevant

scientific community• No guidance on reliability• Jury decides if it can be used

Daubert v. Dow (1993)• Admissibility is determined by

• If theory is unique or can be tested• If science has been offered for peer

review• If rate of error is acceptable• If the method at issue enjoys widespread

acceptance• If the opinion is relevant to the issue• Judge decides if the evidence can be

used

Types of Evidence

“You can learn a lot byjust watching.”

-Yogi Berra, former NYYankees catcher and sage

Types of EvidenceTwo general type:• Testimonial – a statement made under oath

• Direct or prima facie evidence

• Physical – any object or material that is relevant in a rime• Indirect evidence• Examples: hair, fiber, fingerprints, documents, blood, soil, drug, took marks,

impressions, glass, etc…

Testimonial evidenceTestimonial Evidence PPT