The authors put forward an analysis of the case of Beaudry ruled by the Supreme Court of Canada. In that case, the Court specified the conditions under which a guilt verdict of obstruction of the course of justice may be rendered against a police officer and ruled on the criterion of an unreasonable verdict.First, the case of Beaudry unanimously sanctioned police discretionary power not to put a suspect under arrest and press forward an inquiry in the public interest. The authors voice their concern that excerpts of the judgment make certain types of offence trite. They underscore nevertheless that the Court did not wish that police officer exercise their discretion on the sole basis of the seriousness of the offence but rather on the distinctive circumstances of its committal, in the interest of justice.Then, the case of Beaudry illustrated the development of two conflicting schools of thought on the role of a court called to revise the discretionary appreciation of the evidence by the trial judge. After having reviewed the case law since its deliverance, the authors concluded that Beaudry directed to the appellate courts a clear invitation to prudence and restraint in their revision of a trial judge's discretion, in spite of the qualified support of a majority of the Supreme Court to a new criterion.