He was taken to an RCMP detachment, finger printed, made to use a breathalyzer, and for the first day or so was unsuccessful in contacting a lawyer.

Sopinka first considered the leading case of R. v. Landry [1986] on warrantless arrests in a dwelling, which held that a police officer could only arrest if there are "reasonable and probable grounds" to believe that the person is on the premises, the proper announcement is made before entering, and that the officer reasonably believes that the person has committed or will commit an indictable offence.

http://csc.lexum.umontreal.ca/en/1986/1986scr1-145/1986scr1-145.pdf Exclusionary rules of evidence based on section 8 violations of the Charter of Rights and Freedoms.

A voir dire is held by the trial judge to review the evidence in question before it is presented to the court or jury.

This helps to ensure that any evidence brought before the courts has been legally seized by the police and that it does not bring the administration of justice into disrepute.