The federal government of canada enacts criminal law under section 91. 27 of the constitution. In canada there are no common law offences, for some thing to be a crime in canada it has to be enacted and written down in the piece of legislation. We talked that most crimes are written in criminal cod of canada but there are other pieces of legislation that has crime in it as well as long as they are federal pieces of legislation. The same rule doe not apply for defenses. So there are no common law offences, but there are common law defenses. So judge tomorrow if i come with a brilliant idea for bringing defense that nobody has heard of, a judge can say that is a fabulous idea and i am going to create a brand new defense in canada. So the defenses can be created and exist at common law.