1. Welcome to Forensic Science!
Today’s Lesson Question:
What is PROBATIVE VALUE?

2. Today’s Objectives Students will be able to:
1) Explain how forensic science differs from other scientific endeavors (and how they are related).
2) Understand the main types of forensic evidence:  motive, eyewitness accounts, physical evidence and trace evidence.
3) Understand the significance of the Federal Rules of Evidence.

3. THE ACTIVITY
In the computer lab investigate the history of forensic science using the website:
Trace major developments in the history of forensic science. 
What events do students consider the most important, and why?  What aspects of forensic science have the most probative value, and why?  

4. THE ACTIVITY
The main types of forensic evidence -- motive, eyewitness accounts, physical and trace evidence
What is the probative value of each. 
How is direct evidence different from circumstantial evidence? 
What makes evidence relevant?  
How is probative value determined?

5. What is Probative Value?
Probative Value-n. evidence which is sufficiently useful to prove something important in a trial.
The Federal government has what is known as the Federal Rules of Evidence manual that is mandatory in all federal cases.
It includes both civil and criminal proceedings.
Many states also have rules  of evidence that are very similar to the federal governments.

6. What are the Types of Evidence?
Direct evidence is evidence that proves a fact or proposition directly, rather that by secondary deduction or inference' (Nemeth, 2001).
Eyewitness testimony and a defendant's confession are both 'direct' evidence.

7. What are the Types of Evidence?
Indirect (a.k.a. circumstantial) evidence is a fact that can be used to infer another fact.
Circumstantial evidence includes body fluids, fibers, and expert witnesses.
Witnesses, physical, direct, indirect, testimony, expert testimony and opinions, documents and hearsay are other types of evidence.

8. The Four Types of Evidence Article
Click here for a link to the article.
Read the article and discuss the following with your partner:
What is the importance of evidence?
What makes evidence probative?
Why is it important to establish rules with handling or using evidence when prosecuting a crime?