A term used to describe a sample of known source taken for comparison purposes.

Example-An elimination sample is one of known source taken from a person who had lawful access to the crime scene (e.g., blood or cheek (buccal) swabs for DNA analysis, fingerprints from occupants, tire tread impressions from police vehicles, footwear impressions from emergency medical personnel) to be used for comparison with evidence of the same type.

A reference sample is material of a verifiable/documented source which, when compared with evidence of an unknown source, shows whether an association or linkage exists between an offender, crime scene and/or victim (e.g., a carpet cutting taken from a location suspected as the point of transfer for comparison with the fibers recovered from the suspect's shoes, a sample of paint removed from a suspect's vehicle to be compared with paint found on a victim's vehicle following an accident, or a sample of the suspect's and/or victim's blood submitted for comparison with a bloodstained shirt recovered as evidence).