Although police in Canada can use polygraph tests – commonly known as lie detector tests – in their investigations, in most cases the results are not admissible as evidence in court.

Polygraph tests in Criminal Court

The Supreme Court of Canada has ruled repeatedly that polygraph evidence is inadmissible in criminal court cases. The case most often cited is R. v. Béland, 1987 in which the Court gave the following reasons for rejecting the results of a polygraph as evidence because they violated several “rules of evidence”, namely:

• the rule against oath helping (which prevents the use of evidence only to prove good credibility of the person taking the test)
• the rule prohibiting the admission of consistent out-of-court statements by a witness: the courts consider using a polygraph test to corroborate out-of-court statements to be similar to having another witness corroborate out-of-court statements, and thus a polygraph test offends the rule against past consistent statements
• the rule against bolstering character: the courts do not allow an accused to introduce evidence relating to specific acts which tend to establish their character, and thus a polygraph test is inadmissible as the results of a test would be tantamount to evidence of specific acts which establish the accused’s character

The Court decision also stated that:

• admitting polygraph evidence is contrary to the expert evidence rule which says that judges and juries are suitably qualified to decide the reliability and credibility of the witness
• the admission of polygraph evidence would cause delays and complications that may disrupt the proceedings

Polygraph tests in civil court

The result of a polygraph test may be admissible in Civil or Family Court, however, judges in these types of cases treat each case individually. The questions and answers on a polygraph test may be admissible in certain situations, for example when an answer constitutes an admission against the party’s interest.  Also, if a witness volunteers or rejects taking a polygraph test this may also be considered as acceptable evidence.

Use of polygraphs by police

As mentioned, it is legal for police in Canada to use polygraph tests in their investigations. Police have a right to search, interrogate and detain potential suspects and witnesses. Under the Canadian Charter of Rights and Freedoms individuals have the right to remain silent. It is important to know that what you say to the police or write down could later become evidence against you.

Get help

To erase your criminal record, call toll-free 1-888-808-3628 or learn more at Pardon Partners. It’s easier than you think.

If the police have asked you to submit to a polygraph test, or you have been charged with a crime, it is important to hire an experienced criminal defence lawyer as soon as possible. Contact our preferred criminal defence expert, Calvin Barry Criminal Lawyers for a free consultation at 1-866-961-4963 .

								
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