Intro to Forensics
We are now ready to explore the fascinating world of forensic sciences.
But what are forensic sciences, and how can sciences help us solve crime? Let's go around and see what everyone has to say about it!
But what are forensic sciences, and how can sciences help us solve crime? Let's go around and see what everyone has to say about it!
A Simple Principle
All forensic sciences are basec on Locard's exchange principle:
"When two objects come in contact, there is always an exchange of materials between them."
We can think of this as, every contact leaves a trace behind. These clues are what help people solve crimes. But forensics are not only used to solve crimes; it's also used for other things, such as identifying people from their bones.
"When two objects come in contact, there is always an exchange of materials between them."
We can think of this as, every contact leaves a trace behind. These clues are what help people solve crimes. But forensics are not only used to solve crimes; it's also used for other things, such as identifying people from their bones.
Trace Evidence
If you ever watched a crime show, you have heard of trace evidence.
Traces are the materials exchanged byt the victim and the person of interest. It can be anything. Below are some examples:
Traces are the materials exchanged byt the victim and the person of interest. It can be anything. Below are some examples:
- Fibers and Hairs: Fibers from a suspect's clothes can be transferred to a victim's body, and hairs from the suspect can be found at the scene.
- Fingerprints: These are unique traces left behind on any surface a person touches.
- Paint: In a hit-and-run accident, paint from the suspect's vehicle can be found on the victim, and paint from the victim's car can be on the suspect's vehicle.
- Soil: Soil from a crime scene can be found on a suspect's shoes or car, and soil from the suspect's location can be at the scene.
- Blood: Blood left at a scene can be analyzed to identify the suspect.
- Footprints: There are whole databases of shoe prints which are used to identify exactly what shoe and what size the person was wearing.
- Tool marks: Tools make marks on different things: On objects such as doors, but also on bones.
- Ballistics: The analysis of the bullet hole can determine the caliber of the gun used in a crime; the shell can be matched to a gun because the striations created are unique.
Chain of Evidence
Chain of evidence is the crucial need for meticulous documentation of evidence from crime scene to courtroom. Many cases have been lost because of shoddy chain of evidence. If a defense lawyer can prove that the evidence was tampered with (or, raise reasonable doubt) then the case may be thrown out of court, even if the dude was guilty.
How do you think this could be done?
How do you think this could be done?
Fingerprints
Facial reconstruction
Entomology
Soil composition
Tool marks
Ballistics
Saliva - ? DNA traces
Facial reconstruction
Entomology
Soil composition
Tool marks
Ballistics
Saliva - ? DNA traces
