Ignorance is no defence.
I personally cannot see what all the fuss is about. I didn't know about the Serious and Organised Crime and Police Act 2005 until about two weeks before it was implemented, and yet Blandshire Constabulary still managed to find time to give me a twenty minute chat reminding me that most of the police powers I had been using were about to go obsolete. As for the Fraud Act, I only found out about it three weeks after it had started, when I tried to arrest someone for an offence that did not exist any more. These are examples of good learning experiences.
All of this moaning about "knowing the law" is typical of the left-wing liberalists who threaten to overthrow our great nation. I support more laws that no one knows about and higher penalties if you raise the defence "huh?"