DO NOW:

Slylock found bones in the trash.

The bull is an herbivore and only eats plants.

The raccoon is an omnivore and eats both plants and animals. The raccoon is the trash tosser.

Name Seat Number

Amaro, Federico 1

Amaro, Juan Jesus Villarreal

2

Artieda, Alexander Sebastian

3

Aviles Cruz, Annahi 4

Balcombe, Madison Aremina

5

Basaldua, Jennifer Allison 6

Basurto, Saul 7

Belmares, Thalia 8

Cortez, Cali Teresa 9

Davis, Desiree Nicole 10

Delgado-Jaimes, Isael 11

Dove, Ashley 12

Garces, Ashleigh Renae 13

Gonzales, Brandon Alexander

14

Gonzalez, Isaiah Contreras

15

Guevara, Giovanny 16

Gutierrez, Aryana Lucia 17

Hernandez-Cardoso, Seydi A.

18

NameSeat

NumberHopper-Aguirre, Tyler

Hyatt19

Kelly, Alyssa Lynn 20

Lof, Darcy Elizabeth 21

Lopez, Alexandria Maria 22

Marcum, Meriel Louise 23

Mares, Eric 24

Maxwell, Telisa De'shon 25

McGinnis, Ashley R. 26

Noriega, Samantha B. 27

Parker, Nathan J. 28

Pena, Belkis S. 29

Perez Medellin, Manuel Fernando

30

Pericoli, Karigan Taylor 31

Ramos, Noemi 32

Stukes, Sharif Letike 33

Torres Gamez, Uriel Adrian

34

Valadez, Adam Anthony 35

Zaragoza, Jesica A. 36

Welcome to 2nd period forensic science!Pick up all materials from the “Do Now” boxes (in the cabinet)

Sit in your assigned seat:

Distinguish between

different types of evidence

Distinguish between

different types of evidence

A – Locard’s Principle2 – Deductive reasoning3 – Testimonial evidence4 – Physical evidence5 – Trace evidence6 – Direct evidence7 – circumstantial evidence8 – class evidence9 – individual evidence

Create a frayer model – work with your expert group.

You will share this with a 9-person team.

I’ll choose the best ones to go on our word wall.

Explain the 7 S’s of CSI’s.

Create a poster that explains one of the 7 S’s of Crime Scene Investigations.

Orange – securing the sceneNatural wood color – separating the witnesses.Green – Scanning the `scene / seeing the sceneYellow – Sketching the sceneBlue – searching for evidenceRed – securing and collecting evidence part 1Purple – securing and collecting ev part 2 (evidence packaging)

Crime Scene Team A group of professional investigators, each trained in a variety of special

disciplines. Team Members

First Police Officer on the scene Medics (if necessary) Investigator(s) Medical Examiner or Representative (if necessary) Photographer and/or Field Evidence Technician Lab Experts

pathologist serologistDNA expert toxicologistforensic odontologist forensic anthropologistforensic psychologist forensic entomologistfirearm examiner bomb and arson expertdocument and handwriting experts fingerprint expert

POLICE OFFICERS are typically the first to arrive at a crime scene. They are responsible for securing the scene so no evidence is destroyed and detaining persons of interest in the crime.

The CSI UNIT documents the crime scene in detail and collects any physical evidence.

The DISTRICT ATTORNEY is often present to help determine if any search warrants are required to proceed and obtains those warrants from a judge.

The MEDICAL EXAMINER (if a homicide) may or may not be present to determine a preliminary cause of death.

SPECIALISTS (forensic entomologists, anthropologists, or psychologists) may be called in if the evidence requires expert analysis.

DETECTIVES interview witnesses and consult with the CSI unit. They investigate the crime by following leads provided by witnesses and physical evidence.

Source: http://science.howstuffworks.com/csi.htm

Crime Scene Personnel

7 S’s of Crime Scene Investigation

1. Securing the Scene– Responsibility of the first responder– Safety of everyone in vicinity is top priority– Evidence preservation is second priority

2. Separating the Witnesses– Avoids collusion– Questions that should be asked include:

Secure the Crime Scene

Questions for Witnesses

• A) When did the crime occur?• B) Who called in the crime?• C) Who is the victim?• D) Can the perpetrator be identified?• E) What did you see happen?• F) Where were you when you observed the

crime scene?

3. Scanning the SceneDetermine if it is a primary or secondary scene• Primary crime scene – The original location of a crime

or accident.• Secondary crime scene – An alternate location where

additional evidence may be found.

Where should photos be taken?Wear protective gear to prevent contamination of crime scene

4. Seeing the Scene

– CSI’s need to see the scene– Photos with and w/out rulers should be taken– Triangulation of stationary objects should be

included for reference points

Photographing the Scene

Take at least 3 shots:1. Midrange shot: show how the item is related to

its surroundings2. Close-up: bring out details of item

• Take 2 close-up shots if marking or measuring device is used

• One shot without device, one shot with device

Mark Evidence with Tents

5. Sketching the Scene– Position of body (if any) and any other evidence– Should be measured from 2 immovable landmarks– North should be labeled and a scale should be

provided– Positions of furniture, doors (inside), shrubs, trees

(outside) should be included

6. Searching for Evidence– Spiral, grid, linear or quadrant patterns should be

used

7. Securing and Collecting Evidence– Proper packaging, sealing and labeling is vital

• Liquid/Arson remains - airtight/unbreakable containers• Biological evidence - breathable containers so it can dry out• Dry item - bindle plastic or paper container

– Must include a evidence log and chain of custody

Packaging Evidence

1. Crease a clean paper and place the evidence in the X position (as shown above).

2. Fold in the left and right sides, and then fold in the top and bottom.

3. Put the bindle into a plastic or paper evidence bag affixing a seal over the opening.

4. Write your name on the seal.

Bindle or Drugests Fold: folded paper used to hold trace evidence: folded paper used to hold trace evidence

Chain of Custody

• Essential to maintain in order to present credible evidence in court, a chain of custody log is essential.

• Original collector: bags evidence properly, labels it properly, seals it and signs the sealed edge.

• Next person to receive evidence signs that they received it (lab technician for example); lab tech opens sealed container at a location other than the sealed edge; after examination, tech repackages , signs log and reseals with new tape/signature.

Chain of Custody

– Indicates every person who has handled the evidence

– Log must be attached to packaging

Evidence Log– Case number– Item inventory number– Description of evidence– Name of suspect– Name of victim– Date/time of recovery– Signature of person recovering the evidence– Signature of any witnesses present during collection

Chain of Custody

• Importance of Chain of Custody

Packaging Dry Evidence

• After evidence has dried, it is packed in a paper bindle (aka druggist’s fold)

• Then it can be put into a plastic or paper container, labeled with evidence tag, sealed and taped with the collector’s signature across the taped edge.

• Control samples must also be obtained from the victim for exclusion purposes.

Evidence Analysis

• Done in forensic labs – the largest is the FBI crime lab

• Forensic lab technicians are specialists – unlike what you see on tv

• Results sent to lead detective who then attempts to reconstruct the crime scene

Drug Chemistry – Determines the presence of controlled substances and the identification of marijuana

Trace Chemistry - Identification and comparison of materials from fires, explosions, paints, and glass.

Microscopy – Microscopic identification and comparison of evidence, such as hairs, fibers, woods, soils, building materials, insulation and other materials.

Biology/DNA – Analysis of body fluids and dried stains such as blood, semen, and saliva.

Toxicology – Tests body fluids and tissues to determine the presence of drugs and poisons.

Latent Prints - Identification and comparison of fingerprints or other hidden impressions from sources like feet, shoes, ears, lips or the tread on vehicle tires.

Ballistics (Firearms) – Study of bullets and ammunition through the comparison of fired bullets, cartridges, guns, and gunpowder patterns on people and objects.

Toolmarks – Examines marks left by tools on objects at a crime scene or on a victim, such as a hammer used to break a door or a screwdriver used to pick a lock.

Questioned Documents - Examination of documents to compare handwriting, ink, paper, writing instruments, printers, and other characteristics that would help to identify its origin.

Investigating the Evidence

What evidence would you collect and how?