That's a pretty weird conflation though. As in, what do narcotics laws have to do with banking regulations? The marijuana scenario describes someone who is breaking a law and is arrested when he is witnessed breaking that law. I don't agree with that law, but it is still a law in most places.
There's much more ambiguity with the Wall Street example. In many cases, it wasn't unlawfulness but greed and cold heartedness. Many of these banks shittily took advantage of the regulatory system and screwed a lot of people over, but it wasn't illegal.