DNA Evidence

1
DNA Evidence

• Presented by
• S.R.O. Di Lorenzo
• Myrtle Beach Police Department

2
What is DNA?

• Deoxyribonucleic acid
• Found in every cell in the body
• A persons DNA is the same in every cell (Blood,
  Hair, Saliva, Skin)

3
How does the Police use DNA?

• DNA collected at a crime scene is compared to a
  known sample
• DNA may be taken from a suspect for comparison
• DNA may be compared to other crime scenes to link
  different unsolved crimes
• May make a person a suspect or excuse a possible
  suspect

4
Where is DNA at a Crime Scene

• It can be found virtually everywhere
• DNA is left everywhere the perpetrator has been
• Victim also leaves valuable DNA evidence behind

5
How is DNA Tested/Compared ??

• CODIS (COmbined DNA Index System)
• DNA profiles entered into the database
• Profiles then compared to the suspects profile
• Profiles are compared to DNA found at other
  scenes to close open cases

6
Scenarios

• Victim receives a threatening letter
• Saliva on stamp is compared to suspects known DNA
  profile
• Baseball hat is found at a crime scene
• What DNA may be found with the hat?
• Your turn!!!

7
Collection of DNA evidence

• BIO-Hazard
• Germs - Pathogens
• Contamination