Bills C-51 (1977), C-17 (1991), and C-68 (1995) were enacted into law by the Government of Canada with a view to tightening controls on firearms in order to prevent homicides related to their use. The effectiveness of these laws has fuelled several debates on the political scene. Given the many limitations of assessments conducted to this day, the credibility of their results is often questioned. Using a multiple-time-series design, the purpose of this article is to assess the impact of the three most recent Canadian gun control laws, all the while overcoming the limitations identified in the scientific literature. Our results show that the enactment of Bills C-51 and C-68 was followed by a significant drop in the number of homicides committed with a firearm, a decrease of 5 percent to 10 percent, depending on the province. This reduction was most noticeable in the case of homicides committed with a shotgun or a hunting rifle. No tactical displacement was observed. Finally, results suggest that the effectiveness of these laws is due to the reduced access and availability of firearms rather than to the severity of sentences provided in the legislation. (Published Abstract)