I know that the rationale behind the 2008 market collapse is off of everyone's radar, for the moment. Still, because we're heading for a similar economic meltdown, this PBS documentary (aired 1-22-13) is instructive because of how it illustrates how high level Wall Street executives became "untouchable" after 2009.
To be sure, lower level workers in the financial sector have been brought up on charges. But procsecuting low level financial fruit is nothing to write home about if the players who signed off on the mess are still running the show.
There's more, but I'll just leave you to watch the documentary.