What is Certiorari

Certiorari is a royal prerogative writ involving a petition made to the sovereign, in Canada in the form of her Superior Court Justices, to quash (not squash) a lower court or government official's decision as having been made improperly. It's especially used where there is no statutory right of appeal provided for. 

Certiorari is sometimes sought in combination with one of two other writs - mandamus or prohibition - in order to force a lower court or official to do a particular thing after an earlier decision has been quashed through certiorari (mandamus) or stop that official from do anything similar in the future (prohibition). 

Why Pursue Certiorari

Certiorari can be an effective means of overturning lower court or official decisions, such as committal for trial after a preliminary inquiry or the issuance of a search warrant by a judge. It's effectively a form of criminal judicial review.

How to Apply for Certiorari

Only a court of "original inherent jurisdiction" has authority under the common law to grant a writ of certiorari, which in Ontario is the Superior Court of Justice. 

Certiorari is sought by way of notice of application and supporting affidavit with exhibits. You don't start it with a notice of appeal, because it isn't an appeal - even though it rather looks like one. You'll need to order transcripts of the lower court hearing if that is what you're challenging, and produce for the reviewing court all exhibits the lower court reviewed.

If the certiorari application concerns a decision like the issuance of a search warrant where there was no lower court hearing then you won't need transcripts, all you'll need is the documentation surrounding the warrant. 

It's possible to appeal a certiorari decision by a Superior Court up to the Court of Appeal. 

Outside the criminal context, certiorari is now usually sought through a Judicial Review of administrative action application to either the Ontario Divisional Court or the Federal Court, depending on whether you are seeking to overturn provincial or Federal government action. Be aware that there can be very limitation periods imposed by statute within which to file a Judicial Review. 

You can learn more about the firm's non-criminal judicial review services at www.acmlawfirm.ca (for all provincial judicial reviews and federal judicial reviews other than immigration and citizenship) and www.compleximmigration.ca (for immigration and citizenship judicial reviews).