Certiorari is a remedy that seeks to have the Superior court of a Province review proceedings in the Provincial Court to determine if the lower court has acted without, or, in excess of its jurisdiction. The applicant seeks to demonstrate that the decision of the lower court either exceeded its jurisdiction or had no jurisdiction to make the decision challenged. If the Superior Court agrees, it quashes the decision of the lower court. The Superior Court may also give directions to the lower court as to how to proceed now that its earlier decision has been quashed.
Mandamus is an extraordinary remedy that is the reverse of an order of prohibition. It seeks to force an inferior court to do something that is one of its duties to perform or within its jurisdiction or competence to perform and should have performed in the circumstances. It may be used, for example, to compel a lower court to hear an application or make a decision in favour of an accused that should have been made upon the initial request of the accused.
Prohibition is an order by the Superior court to prevent an inferior court from exceeding its jurisdiction or from continuing to exceed its jurisdiction. It is therefore generally a preventative measure. Occasionally, an order of prohibition may no longer be available once the unlawful decision has become final. It may be used, for example, to prevent the court from proceeding with a trial when the inferior court has improperly refused to grant an order that, as a matter of law, it was required to make.
The above is the an excerpt of Patrick J Ducharme’s book, Canadian Criminal Procedure, available at Amazon or in bulk through MedicaLegal Publishing along with Criminal Trial Strategies.
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