Fall Forensics Final

Sequence of decomposition:

Fresh, bloated, active decay, advanced decay, dry decay

What is the rigor mortis timeline?

Full or peak rigor - 8-12 hours Rigor left body - 24-48 hours

What are the types of crime scene search patterns?

Grid, linear, quadrant/zone, and spiral

How are insects useful to solving crimes?

Help determine PMI, if the body has been moved, and cause of death

What are the 5 manners of death?

Homicide Suicide Natural Accidental Undetermined

When are fingerprints formed?

In utero, very early in pregnancy - volar pads are formed which form the friction ridges. The formation of these ridges are dependent upon the environment of the fetus.

Why isn't insect evidence collected more often at crime scenes?

Investigators may not be prepared to collect or have knowledge of how or what to collect.

Why should witnesses be separated at the crime scene?

Keep them from talking to one another so they can't "get their stories straight"

Which fingerprint classification is the most common?

Loop

3 Classification of fingerprints?

Loops Arch Whorl

Who performs an autopsy?

Medical examiners, pathologists, sometimes coroners

How should you store wet or damp collected evidence?

NO plastics or metal containers Paper allows the moisture to evaporate

Identify the type of fingerprint:

Plain arch

Identify the type of fingerprint:

Plain whorl

What is the difference plastic, latent, and patent fingerprints?

Plastic prints - usually left in something like mud, dough, paint wax soap Latent prints - can't be seen by naked eye, power must be used to make them show up so they can be lifted Patent prints - made by a liquid, like blood, or a powder that sticks to the finger and then transfers to a surface. Ink, blood, dirt, flour, grease,

Identify the type of fingerprint: on the left hand

Radial loop

7 S of crime scenes

Scan Secure Separate Photograph Document Sketch - make sure to have 2 reference points for triangulation

Timeline for food to empty from stomach and out the body

Stomach: 2-6 hours Small intestine: 12 hours Large intestine: 14 hours

Identify the type of fingerprint:

Tented arch

What is algor mortis?

The cooling of the body after death until temperature of environment

What is the purpose of The Innocence Project?

To reopen cases where eyewitness testimony and/or DNA evidence can clear someone who has been wrongly convicted of a crime.

Explain Locard's principle of exchange

Trace evidence can be exchanged between a suspect/victim and or the crime scene/victim/suspect. Basically you take something with you or leave something at the crime scene. Intensity, duration of the contact will determine how much trace evidence is left behind

Identify the type of fingerprint: on the right hand

Ulnar loop

Which is less reliable in determining TOD if person has been dead less than 12 hours? Rigor mortis Livor mortis Potassium levels in the eye Algor mortis

potassium levels in the eye

Types of evidence: direct

seeing is believing

What is the function of maggot spiracles?

1. Can be used to determine the age of fly species to help determine TOD/PMI 2. breathing

Body temperature is lost at ________ degrees Fahrenheit with mild/ normal conditions

1.4 degrees/hour

Henry System:

16 Right Index 8 Rt. Ring 4 Lt Thumb 2 Lt Middle 1 Lt Pink +1 16 Right Thumb 8 Right Middle 4 Rt Pinky 2 Lt Index 1 Lt Ring +1

Minutiae that helps identify what type of print someone has, contains two deltas. What kind of print is this?

A whorl

Identify the type of fingerprint:

Accidental

Another name for grave wax?

Adipocere: Waxy material formed from the breakdown of fat under dry conditions

What component of fingerprints react with ninhydrin?

Amino acids

What are the most common types of insects that feed on a corpse?

Ants, butterflies, yellow jackets, beetles

What is AFIS?

Automated fingerprint identification system

Marbling of the skin occurs during decomposition:

Because of the blood being broken down by chemical reactions of sulfur and hemoglobin

Describe/define livor mortis

Blood settling Purple color Blanching occurs until fixed Decomp of blood cells and blood vessels

Identify the type of fingerprint:

Central pocket loop (whorl)

Types of evidence: indirect

Circumstantial: Biological, Physical, fingerprint

What is the protocol for collecting evidence?

Correct packaging methods Documentation of the evidence in evidence log Sign in/sign out to maintain proper chain of custody

What should be included in a crime scene sketch?

Date and location of crime scene North symbol Scale Who is drawing the sketch

Why is the use of fingerprints for identification purposes not exact?

Depends on humans carrying out he analysis and humans make mistakes

Identify the type of fingerprint:

Double loop (whorl)

Order of development for blowflies

Egg-larval stages of instar 1, instar 2, instar 3-pupa- adult Did you know that blowflies are attracted to urine and feces? Blowflies are NOT active at night and only grow because of available heat or degree hours. This is why we can't take into consideration their development at night.

What kind of information does a forensic scientist provide in a court of law?

Factual data usually concluded from testing and analyzing evidence from crime scene