I have much doubt that criminal penalties would change anything. People would just put much more energy in avoiding them. I think that state a priori regulation is a more effective tool than state a posteriori punishment.
> "You put Lloyd Blankfein in pound-me-in-the-ass prison for one six-month term, and all this bullshit would stop, all over Wall Street," says a former congressional aide. "That's all it would take. Just once."