DNA testing in crime works by comparing DNA profiles from crime scene evidence to suspect DNA profiles and DNA databases to identify potential suspects.
The Process of DNA Testing in Crime
The process generally involves several key steps:
- Evidence Collection: Biological material (e.g., blood, saliva, hair) is collected from the crime scene.
- DNA Extraction: DNA is extracted from the collected biological material.
- DNA Profiling: A DNA profile is created from the extracted DNA.
- DNA Database Search: The DNA profile is then searched against a DNA database, such as the Combined DNA Index System (CODIS).
- According to the reference, Crime Lab scientists analyze evidence and develop a DNA profile of a possible suspect. That DNA profile is used to search the DNA database, known as the Combined DNA Index System (CODIS).
- Match Identification: If the DNA profile matches a profile already in the database, it's called a "hit." This indicates a potential suspect or links the crime to other cases.
CODIS: The National DNA Database
CODIS (Combined DNA Index System) is a crucial component of DNA testing in crime.
- It's a national DNA database maintained by the FBI that contains DNA profiles from convicted offenders, arrestees (in some states), and forensic samples.
- The database is used to search for matches between crime scene DNA and known individuals.
- According to the reference, if the DNA sample searched against CODIS matches a DNA sample already in the database, that is known as a “hit.”
Benefits of DNA Testing in Crime
DNA testing provides numerous benefits in criminal investigations:
- Identification of Suspects: It can identify potential suspects by matching crime scene DNA to individuals in DNA databases.
- Exoneration of the Innocent: DNA evidence can clear wrongly accused individuals.
- Linking Cases: It can link different crimes together based on matching DNA profiles.
