Financial fraud is one aspect of Game Theory that is glossed over. This is because cheating, whilst being at the very heart of applied Game Theory, is at the same time best used pursuant to Game Theory when it is NOT declared or acknowledged.
The ultimate form of cheating is not to ignore the rules. It is to be totally conversant with the rules, whilst at the same time denying as much knowledge of the rules as possible to everyone else.
This is the zen of being a lawyer.