Course title

none

Pre-requisite

Biology

Course description

Forensic science is the application of basic biological; chemical and physical science principles and technological practices to the purposes of justice in the study of criminal and civil issues. In this class; emphasis is on understanding the underlying scientific theories of forensic science; with special emphasis on the basics of chemistry. The class will build upon the student?s prior knowledge of biology and chemistry; using analytical chemistry techniques to analyze and identify trace evidence; including DNA. Students will evaluate the constituents of materials by organic; inorganic; and biochemical analysis; and use their academic and laboratory skills to develop a deeper understanding of science. This class prepares students to further their science education at the university level; and introduces them to the possibilities of a science related career. Major themes of study in this course are pathology; anthropology; odontology; ballistics; trace evidence; biological fluids; DNA; fingerprints; impression evidence; questioned documents and forensic psychiatry/psychology.
WEEK UNIT LAB TIME (Hours)
First Semester
1 Introduction Shredded paper reassembly 3
2 Evidence Observational skills (suspect ID) 1
3 Evidence Microscope introduction 2
Chromatography introduction 1.5
4 Crime scene Mapping of a crime scene 3
5 Fingerprints Prints (completing print card) 1
Lifting (powder on different surfaces) 2
6 Fuming (Cyanoacrylate; Iodine) 1
Classifying (Henry?s classification) 2
7 Matching prints with suspect 2
9 Hair Hair comparisons 3
11 Fibers Wayne Williams case history investigation 1
13 Fiber burning analysis 1
Solvent solubility 1
14 Documents Handwriting analysis 1
Match handwriting to suspect 1
15 Ink chromatography 2
16 Drugs Spot test lab (Initial drug identification) 1
17 Unknown powder Lab (Aspirin I.D.) 1.5
Second Semester
1 Toxicology Lead detection 1
3 Soil Soil profile (Soil comparisons) 2
4 Soil density gradient tube 1
Soil particle size profile 1
Tire track casting 1
5 Glass Direction of force 1
6 Glass density lab 2
7 Serology Blood typing 1
8 Blood identification (Luminol) 1
9 Blood spatter analysis 2
10 DNA Analysis DNA extraction 1
11 Electrophoresis lab 2
12 RFLP simulation 2
13 Entomology Time of death (Insect life cycles) 10
15 Anthropology Height; sex; and age determination 2
17 Firearms Test for lead residue 1
Bullet comparisons 1

Glass Density Lab:

Background Information
A man; let?s call him Calvin; parked his car on the street in front of his house. While he was inside watching Oprah; someone crashed into his prized automobile and then drove away without telling anyone. Calvin heard the crash; rushed outside (during a commercial); and found that his car was ruined. Calvin immediately (during another commercial) called the police. When the police arrived (Detectives Sullivan and Carlson); Calvin made them wait until Oprah was over (Dr. Phil was on!) and then he told them what happened. The police took one look at Calvin?s car and asked ?How did one little accident cause this much damage?? Calvin had to explain that his car was already a piece of junk before it got hit and he was just hoping to score a big insurance claim. After offering the detectives coffee and doughnuts Calvin was able to convince them to investigate the ?Crime of the Century?. Calvin was thinking that the police would take fingerprints; blood samples; DNA samples; interview witnesses; and maybe shoot the neighbor?s dog; but they didn?t do any of those things. Instead; they swept up a small pile of glass that was on the ground near the fender of his car and left. Calvin thought that this was pretty weird; but he wasn?t too concerned as he was planning to retire on the insurance settlement and spend the rest of his life watching Oprah re-runs. After about a week; the detectives returned and gave him a list of suspects:
Suspect Designation _____ __Name__________ Type of Automobile
A Taylor Nelson Red Porsche
B Casey Jones Rusty Volkswagen
C Shenae Rey Yellow School Bus
D Kami Shelton Pink Cadillac
E Heajin Yu Hundai

Calvin told the detectives that it must be Heajin because everybody knows that she can?t see very well and tends to hit things a lot. The detectives nicely told Calvin to sit down; shut up; and take his hat off in class. They then explained that in order to find out who the crazy driver was they needed to compare the glass found at the accident with the headlight glass of each of the suspect?s cars. The easiest test to do was a density test. As everyone knows; the density test will only put the glass in a certain group (It?s a Class Characteristic) but Calvin slept during that part of his forensics class so he was clueless.

Materials
Glass samples taken from the headlights of the suspect?s vehicles
Graduated cylinder Scale
Forceps Water
Paper towels
Procedure
1) Place glass sample on the scale and determine its mass in grams. Record on chart.
2) Place 20 ml of water in the graduated cylinder. Measure carefully!
3) Add the glass sample to the graduated cylinder and record the new volume in ml.
4) Do each sample twice with different pieces of glass.
5) Repeat for all five suspect glass samples
6) Calculate the volume of water displaced by the pieces of glass by subtracting the value in column one from the value in column two.
7) The density of the glass is determined by dividing the mass by the volume.

1. Original volume
in graduated
cylinder 2. Volume after
glass was
added 3) Subtract col. 1
from col. 2
4) Mass of
sample
5) Density of
sample

Glass on ground

Suspect A

Suspect B

Suspect C

Suspect D

Suspect E

Questions
Please answer in complete sentences
1) Which suspect glass most closely matches the glass found at the accident scene?
2) Does this prove without a shadow of a doubt that the suspect is guilty? Why or why not?
3) Water has a density of 1g/ml. Is the density of your glass samples more or less than water? On what do you base your conclusion?
4) What are the possible sources for error in this experiment?

School country

United States

School state

Arizona

School city

Phoenix

High school

Deer Valley High School

School / district Address

20402 N 15th Ave

School zip code

85027

Requested competency code

Lab Science

Date submitted

Approved

Yes

Approved competency code

  • LINT
  • Integrated science

Approved date

Online / Virtual

No