It's an interesting idea but the trouble is copyright laws can really only be applied on a geographical basis. So they could be used to pursue individual purchasers of illegal files. But I can't see the police bothering to do that - or that they should really. It's just like peddling dope -- we should be aiming at the suppliers, not the users. And in the case of IP theft they are all beyond the law, in countries that don't much care about digital theft. 

I suspect we're beyond the point where the law can deal with this. We need to explain the situation clearly and honestly to the book buying public and hope they'll see it's in their interests to buy what they consume. The real thieves already have their noses into the trough of stolen books, music, videos, games and software. They're not going to change.