I'm pretty skeptical of these prosecutions. Even fines that wind up in the billions don't dent the profitability of the large banks. They seem to see legal action as part of the cost of doing business, and they're still making obscene amounts of money, so from their perspective, if it ain't broke... Until DoJ starts to get really punitive against the bottom line and bank executives themselves, it's going to be business as usual.
And how many of them are actually going to see the inside of a jail cell?
Some crimes need to have an addendum on any sentencing that includes a 'No buy your way out of jail' clause.