A great way to discourage all kinds of unethical, illegal and outright disastrous behavior is to bring back the top marginal tax rate to 91% (or at least 71%).

Under Republican Eisenhower, people were taxed at a lower rate on their first 3 million (in today's dollars) and then at 91% on every dollar after that. Creativity and hard work were NOT stifled. The only thing that stopped was depressions and huge bubbles and crashes and bank failures.

It's beyond obvious at this point, and it would do what so many failed, half-assed and non-existent regulations haven't done.