Skip to content

Preservation of Evidence

Preservation of evidence laws requires government agencies to keep evidence that may contain biological material. More than half of the states have preservation of evidence statutes. Montana’s statute requires the agency to maintain evidence for a minimum of three years after a conviction. 

Why is preserving evidence important? 

  • The results of biological testing can improve a defendant’s innocence claim. 
  • If the case was tried prior to the advent of forensic DNA testing or with an early or outdated form of DNA testing, having the preserved evidence would allow forensic analysts to conduct tests now.
  • If DNA testing was never conducted before the original trial even though advanced testing techniques that could identify the perpetrator were available, having the preserved evidence would allow forensic analysts to conduct tests now.