Forensics unit 1

Medical Examiner

A person with a medical degree and legally trained in autopsy

Corenor

An ellected official who signs death certificates

Forensic Science

application of science to the criminal and civil laws that are enforced by police agencies in a criminal justice system

Which type of case is typically where forensic science is used in the court room

Criminal cases

Expert Witness

expert in a field, certifies if possible

Manner of death

natural, accidental, suicidal, homicidal, undetermined

cause of death

disease, physical injury, stroke, heart attack, bludgeoning, shooting, suffocation

Mechanism of Death

The specific change in the body that brought about the cessation of life. Ex. exsanguinations (blood loss), Pulmonary arrest (heart stoppage)

Frye case

debate on admissibility of lie detector can it be trusted… Result: generally accepted by the science community=accepted by court

Daubert case

“good” science vs Pseudscience is determined by the judge with the guidance of the scientist

pros of frye standard

Confidence that its valid because the majority of the population agrees

cons of frye standard

new science not accepted

Pros of Daubert standard

New tech can be used

cons of daubert standard

Judges are not scientists, and also the judges can have a bias

Binding Precedent

A decision from a higher case that must be followed by lower courts in similar cases (Federal court vs state or county cases)

Melendez-Diaz case

Cocaine seized, Sample confirmed to be cocaine in lab. Melendez accused guilty but his lawyers claimed his 6th amendment right to face the accuser was violated, this case went to U.S supreme court and now as of 2009 defense can require accuser to come to court.

Crime Labs

Very basic like any research lab

1st crime lab in US

in los angeles cali

Largest crime lab

FBI crime lab in DC

Bertillion

Anthropometry= measurment of man, first to take mug shots and record scars, tattoos, and birthmarks to aid investigations

Edmond Locard

WW!- analyzed stains and dirt on uniforms to identify where a soilder died, he also identifies metal fragmens in the pockets of coin counterfitters and successfully identified the jobs of 92 of 100 individuals by the dust on their eyebrows.

Locard’s Exchange Principal

A criminal leaves something behind at a crime scene and also takes something away with them, evidence is transformed and exchanged between the crime scene and the criminal.

Who’s the first to arrive at a crime scene?

Police and EMTs

Order of crime scene

1. Ensuring safety and perserving life

2. Securing and controlling the crime scene

3. witnesses

4. Record the scene w photos or sketch

Record keeper or note taker

The first to walk through a scene; notes everything and leaves nothing to memory. Written in permanent inc in a spiral notebook to ensure nothing is added or removed.

Photographer

Photographs everything; evidence, surroundings, possible exits, entrances, etc.

Rough sketch

Shows lengths (traingulation), labels, legend, body, NOT TO SCALE, name, date, time, location

Final sketch

computerized, straightened up, drawn up to scale

Why do we need to use a paper bag when packaging anything with blood on it

to prevent moisture and mold

packaging powder

druggist fold or plastic zip lock

what must be packaged airtight

charred debris

How to package hair

Druggist fold, sealed edges, and openings with scotch tape or adhesive tape

How to package soil

Paper bags, seal to prevent loss

How to package glass fragments

Wrap each piece seperately. Pack in strong box to prevent shifting and breakage. Identify contents.

Rigor mortis

within the first 24 hrs, disappears after 36 hours… muscles relax and become rigid

Livor mortis

blood settles in the parts of the body closest to the ground, begins immediately and continues for the first 12 hrs

Algor mortis

body tempature cools untill reaches room tempature; after hour 1 the body generally decreases tempature by 1-1.5 degrees farenheit per hour

Referance samples

biological or physical sample collected from a individual to compare against unknown evidence found at a crime scene

Chain of custody

the chronological paper trail and documentation that tracks the sequence of collection, control, transfer, analysis, and storage of evidence or materials from the moment they are retreived untill they are presented in court.

Biology Unit

examines DNA, dried bloodtsains, body fluids, hairs, fibers, and bontanical materials.

Firearms unit

examines firearms, bullets, cartridge cases, shotgun shells, ammunition, and gunshot residue

Document Examination unit

Examines handwriting, typewriting, paper, indented writing, erasures, and document identity

Photography unit

Photographs and records physical evidence using digital, infrared, ultraviolet, and x ray techniques

Latent fingerprint unit

Processes and examines evidence for hidden fingerprints

Polygraph unit

Uses a lie detector to assist criminal investigations and interrogations

voiceprint analysis unit

Compares voice sound patterns to help connect a voice to a suspect

Crime scene Investigation unit

Collects and preserves physical evidence at crime scenes for laboratory analysis

Toxicology unit

Examines body fluids and tissue for drugs, alcohol, poisons, and other chemicals to determine their presents and effects

Anthropology

Studies human remains and bones to help identify individuals and determine age, sex, and possible cause of injury

Criminalistics

Examine physical evidence such as DNA, blood, hair, fibers, drugs, bullets, and glass

Digital and multimedia sciences

Examines digital evidence from computers, phones, videos, and other electronic devices

Engineering and applied sciences

Uses engineering and science to investigate accidents, failures, and physical evidence

Jurisprudence

Focuses on Law related to forensics

Forensic nursing science

Provides healthcare and collects evidence from patients involved in crimes, abuse, or assault

Odontology

Uses dental evidence to identify individuals and examine bite marks