Chain of Custody
Chain of custody refers to the movement and location of evidence from the
moment it was collected to the time it is presented at trial. A proper
Chain of Custody must establish:
- Which person / officer / investigator collected the evidence and what did
that person do with it for example, did the investigator package the evidence
so it prevents tampering and distinguishes it from other evidence seized
at the same crime scene;
- Date, time, and place the evidence was collected;
- How the evidence was collected - what procedures and methods were used
to collect it and what safeguards were used to protect the evidence;
- How the evidence was tagged, labeled or marked;
- Where the officer / investigator stored the evidence and properly logged it.
- When and by whom the evidence is moved, transferred, or tested.
Testimony and documentation are used to authenticate evidence – to
establish that the evidence is what it is claimed to be. Evidence that
cannot be authenticated may not be reliable or trustworthy and will not
be admitted at a criminal trial. Often, prosecutors must establish chain
of custody because criminal prosecutions depend on evidence gathered by
police officers at the crime scene. Criminal defense attorneys generally
challenge the chain of custody presented by prosecutors. If a criminal
defense attorney succeeds in showing a break in the chain of custody then
the prosecutor may be precluded from presenting that evidence to the jury.