Suicide accounts for approximately 4000 deaths a year in Canada, of which about 16% of those are suicide using a firearm. Canada has undertaken legislative efforts to regulate and control firearms, Bill C-51 in 1977 and Bills C-17 and C-68 in 1991 and 1995. Regulatory approaches that decrease the availability of firearms are hypothesized to reduce suicide by firearm however the substitution effect suggests it is possible that people may substitute other methods of suicide in place. Canadian studies on associations between legislation, regulation, and suicide rates have been published over the last three decades, and a search revealed thirteen that met the criteria. Seven studies examined the association between Bill C-51 and suicide rates and found that while rates of suicide by firearm appeared to have declined in association with regulations, there appears to be a substitution effect into other methods and no overall change in suicide rates. Six studies examining the effects of Bill C-17 and C-68 revealed a decrease in the rates of suicide by firearms, with a corresponding increase in non-firearms suicide rates and no decrease in overall suicide rates. One study even suggested no associated decrease in firearm suicide rates with an increasing rate of suicide by hanging possibly due to changes in preferences. These results suggest legislation has mixed effects on firearm suicide rates and may not alone reduce overall suicide in Canada.