I'm going to answer, since I am conducting a research program on the prevention of trauma caused by firearms.
First, I have a great deal of respect for Mr. Mauser. He has done excellent work on firearms and there are two studies that are repeatedly cited in which he assesses the effect of Bill C-51 on robberies and homicides. That said, you have to be careful when you make associations. If we're talking, for example, about a trend in homicide rates or robbery rates, we can't associate that trend with the measures put in place by the government to combat firearm-related homicides and suicides.
In my opinion, and from experience, you have to know that Professor Mauser has done no studies on the impact of Bill C-68. We have conducted studies in accordance with the same statistical methods, which were very rigorous, and we came to the conclusion that, since Bill C-68, there has been an average of 50 fewer homicides a year and 250 fewer homicides a year committed by firearms, without any tactical displacement effect.