Oh, I know he doesn't. But they do to the various courts in every province.
Say Montreal, at the behest of the Federal Libs, adopts a hand gun ban and someone is arrested under it. They go to court and the defence lawyer defends on the basis that the by-law is null and void as being outside the powers of Montreal to adopt because neither their Charter nor the provincial municipal act applicable provides for the power to adopt such by-law and the Federal enabling legislation is also null as a constitutional infringement in provincial constitutional powers. I am willing to bet the courts are much much more likely to come down on the side of the defence because the number of cases where the Supreme court confirmed municipal law as being a provincial jurisdiction is simply overwhelming. On the other hand, if the Feds try to argue that it is part of their criminal law power, then the court can say: "Fine, then don't delegate it illegally to the municipalities or the provinces. Exercise your own powers yourself." Same result.