You may have seen the movie “Double Jeopardy” about an accused and a murder. There is a very old principle of criminal law that an accused may not be charged twice for the same offence because that would place the accused in jeopardy twice. Since about 1900 in Canada, criminal lawyers have also been applying principles barring relitigation of issues in criminal cases. This is called “issue estoppel,” meaning that the relitigation of the issue or fact is estopped, or stopped, because the issue has already been decided in a previous criminal proceeding.
For example, an accused may be charged with separate and distinct offences but both offences arise from the same alleged facts. If the accused is acquitted of one of the charges, the court has made a finding that the alleged facts sustaining the charge were not proven. The issue of those alleged facts has been determined. The Crown is, therefore, estopped from relitigating this issue in the second charge. Usually, the second charge is withdrawn. The test is that the question of fact in both offences must be vital and fundamental to convicting the accused.
A decision from a jury trial, rather than from a judge alone trial, is problematic for issue estoppel when a general verdict of not guilty is rendered since it is not be possible to determine on which issue the jury based its verdict.
Issue estoppel in criminal law is not reciprocal as it is in civil law where it can be used by both sides of a dispute. It is not available to the Crown. It is solely a defence for the accused.