Torturing the law
These lawyers who write excuse letters for Bush are Corporate lawyers. In fact, they are the worst sort of corporate lawyers.
The good type of corporate lawyer advises their client (the company that hires them) on whether any action the company wants to take is allowed within the law. If it isn't then the client doesn't do it.
The bad type of corporate lawyer advises their client on the best way to make what they want to do look legal. If they are good enough at torturing the law the client can get away with whatever they want.
Gonzalez tortured the law so that Bush could torture everyone else.