Introduction to FORENSIC SCIENCE

Introduction to FORENSIC SCIENCE

CHAPTER 1

What is Forensic Science?

The study and application of science to matters of law.

Includes the business of providing timely, accurate, and thorough information to all levels of decision makers in our criminal justice system

What does a Forensic Scientist Do?

1. Evaluate the Crime Scene

2. Reconstruct the crime

3. Find the evidence left at the crime scene

4. Collect the evidence

5. Use forensics to solve the crime

Criminalistics vs. Criminology

Criminalistics:

The science dealing with the detection of crimeand the apprehension of criminals

Criminalistics vs. Criminology

Criminology:

Includes the psychological angle, studying the crime scene for motive, traits, and behavior that will help to interpret the evidence.

Crime Scene Team (C.S.I.)

A group of professional investigators, each trained in a variety of special disciplines

Crime Scene Team

Team Members:

1. Police Officers

2. C.S.I. /Forensic Specialists

3. Detective

4. Coroner/Medical Examiner

5. Prosecutor

Crime Lab History

1. First police crime lab in the world was established in France in 1910 by Edmond Locard

The famous Locard Exchange Principle that "every contact leaves a trace" is named for him, after Locard solved a strangling case by using fingernail scrapings.

2. First police crime lab in the U.S. opened in 1923 in Los Angeles

3. The Scientific Crime Detection Lab was founded in Evanston, Illinois in 1929

4. The first FBI crime lab opened in 1932

Organization of Crime Labs

Crime Laboratories

1. Approximately 350 in the US

2. FBI maintains the largest and best equipped US laboratory

3. Others are maintained by the Drug Enforcement Administration (DEA), the Department of Treasury - Bureau of Alcohol, Tobacco, and Firearms (ATF), and the US Postal Service

4. Physical Science Unit:

Incorporates the principles of chemistry, physics, and geology to identify and compare physical evidence.

5. Biology Unit:

Applies the knowledge of biological sciences in order to investigate blood samples, body fluids, hair, and fiber samples.

6. Firearms Unit:

Investigates discharged bullets, cartridge cases, shotgun shells, and ammunition.

7. Document Examination Unit:

Provides the skills needed for handwriting analysis and other questioned-document issues.

8. Photography Unit:

Examines and records physical evidence

Optional Services Provided by Full-Service Crime Labs

9. Toxicology Unit:

Body fluids and organs are examined to determine the presences of drugs and poisons.

10. Latent Fingerprint Unit:

Processes and examines evidence for latent fingerprints.

11. Polygraph Unit conducts polygraph or lie detector tests.

12. Voiceprint Analysis Unit:

Attempts to tie a recorded voice to a particular suspect.

13. Evidence Collection Unit: Dispatches specially trained personnel to the crime scene to collect and preserve physical evidence.

Areas of Forensic Science

1. Forensic Medicine:

A. The application of medicine and medical science tolegal problems.

B. MD with a certification inpathology and/or forensicpathology

C. Most are medical examiners

D. Attempt to determine the medical cause of death, mechanism of death and manner of death.

2. Forensic Anthropology:

A. The study of skeletal remains/fragments. Of the 206 bones in human body, the skull is the most useful.

B. Called into identify bodies of mass destruction (crash or genocide)

C. Maintain data bases on bodily structures related to race, sex, age, and stature.

D. May do reconstructive processes (face).

3. Forensic Odontology:

A. The application of dentistry to human identification problems.

B. Used in cases where the body is unrecognizable.

C. Identification based on dentition (teeth enamel)

D. Analyze and compare bite mark evidence.

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4. Forensic Toxicology:

A. The determination of toxic substances in human tissues and organs.

B. Investigates the role agents may have played in causing or contributing to the injury of death of the person.

Scientific Method

1. Observe a problem or questioned evidence and collect objective data.

2. Consider a hypothesis or possible solution.

3. Examine, test, and then analyze the evidence.

4. Determine the significance of the evidence.

5. Formulate a theory based on evaluation of the significance of the evidence

U.S. Laws

1. The U.S. Constitution:

The supreme body of laws that governs our country.

2. Statutory Law:

Legislative acts declaring, commanding, or prohibitingsomething.

3. Common Law or Case Law :

The body of law made up ofjudicial opinions andprecedents.

4. Civil Law:

Deals with non-criminal suitsbrought to protect or preservea civil or private right or matter.

5. Criminal Law:

Regulation and enforcementof rights setting the acceptablelimits of conduct in society

6. Equity Law:

Remedial or preventive such asinjunctions or restraining orders.

7. Administrative Law:

Laws created by agencies suchas the IRS.

Individual rights are guaranteedby the Bill of Rights.

An individual can not be arrestedwithout probable cause.

Miranda Rights

Rights guaranteed by theConstitution.

The police must advise an arrestee of their rights.

Especially the right to remain silent and the right to an attorney.

Types of Crimes

1. Infraction:

Violation of a rule or law that is not punishable by prison.

Examples:

Littering

Traffic Violations

2. Misdemeanor:

Punishable by no more than one year in jail.

Examples:

Shoplifting Vandalism

Simple Assault

3. Felonies:

Serious crimes and punishment ranges from five years to life in jail or the death penalty.

Examples:

Arson

Homicide / Rape

Aggravated Assault

Federal Rules of Evidence

In order for evidence to be admissible, it must be:

1. Probative:

The level at which evidence provides proof of the crime

2. Material:

Address an issue that is relevant to the particular crime

Admissibility of Evidence

1923 Frye v. United States

Scientific evidence is allowed into the courtroom if it is generally accepted by the relevant scientific community. The Frye standard does not offer any guidance on reliability. The evidence is presented in the trial and the jury decides if it can be used.

1993 Daubert v. Dow

Admissibility is determined by:

-Whether the theory or technique can be tested

-Whether the science has been offered for peer review

-Whether the rate of error is acceptable

-Whether the method at issue enjoys widespread acceptance.

-Whether the opinion is relevant to the issue

The judge decides if the evidence can be entered into the trial

Facets of Guilt

Try to prove:

1. Means:

Person had the ability to do the crime

2. Motive:

Person had a reason to do the crime (not necessary to prove in a court of law)

3. Opportunity:

Person can be placed at the crime.