What is considered evidence and how is it used?


There are different kinds of evidence that officers might collect. These include:

  • Physical evidence - like fingerprints and footwear impressions

  • Trace evidence - blood, fibre, and/or hair which might be sources of DNA to identify a person

What happens to the evidence?

The evidence is collected at the crime scene by the Identification Unit, catalogued and entered into the computer by the exhibit officer. Some of it is stored so that it can be accessed later. Exhibits from the scene are processed and stored in a place which is physically separate from the place where exhibits or evidence from the accused are stored. It would be typical to have 80 to 150 pieces of evidence from the crime scene.

Where is the evidence tested?

Some of the evidence may be sent to specialized RCMP laboratories across Canada for testing. The employees of these labs are civilians who have specialized knowledge in their fields, such as:

  • The RCMP toxicology lab - tests and issues reports on drugs or alcohol in the victim’s system.

  • The RCMP chemistry lab - conducts fibre comparisons.

  • The RCMP biology lab - DNA work comparing blood staining on the accused’s clothing to the blood type of the victim or identifying the origins of a hair.

  • The RCMP firearms section may attend the scene and be able to establish the trajectory of a bullet.

Why does it take so long to test the evidence?

There are several reasons why it can take a while to test and process evidence:

  • Lab location - Labs are located in Halifax, Vancouver, Calgary, and Winnipeg. The further evidence needs to be sent to be tested in a specialized lab, the longer the wait. 

  • Types of tests/number of suspects - Testing of blood samples can take months because a series of tests is run, perhaps with blood from a number of suspects.

  • Review process - A specialist needs to verify the results of a test before they can be turned over to the investigators. A second person needs to verify that finding.

What happens if some of my personal belongings are taken as evidence?

Some of the things seized from the scene can be released quite easily. Most are not significant to the investigation. However, if an item is critical to the conviction of the suspect, it cannot be released without the authorization of the Crown attorney or the Medical Examiner for 20 years. Police officers are only the gatekeepers of evidence; they are not authorized to make decisions about the release of property. 

The exhibit officer collects all the exhibits and maintains them. With modern technology and computer programs, he or she makes this information available to many police officers. 

If you have a question about the location of any of your personal property that has been seized, this information can be quickly accessed. Contact the investigating officer to get information about your items. 


Mennonite Central Committee Canada. (2011). Getting through the maze: A guidebook for survivors of homicide.


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