Bharara will go to any length in terms of aggressive and evil as long as it serves his career, from the looks of this
Let's check the facts:
-BTC is not illegal
-Silkroad per se was not illegal, it was a site where legal and illegal stuff was traded
-BTCKing sold legal bitcoins to users of a legal site. Whether BTCKing did comply with regulations when he sold a maximum of $1000 worth of BTC to anonymous counterparties, I don't know. Maybe BTCKing should have registered as a money transmitter? Maybe that part was not even clear in 2012? Hard to tell.
-Bitinstand obviously sold BTC to BTCKing, but not anonymously. This would be like bank A doing business with bank B. Bank A does not comply with regulations or has some customers that use cash withdrawn at their ATMs that are located in bad areas, for illegal purposes, and bank B is made responsible because they delivered the cash to fill these ATMs. The prosecutors would claim that bank B must have known that a lot of cash in these areas is used to buy drugs etc. Insane? Not from the viewpoint of insane minds.
-Advice from Bitinstant to BTCKing to split cash deposits is not illegal itself, in fact thousands of people get their bank accounts blocked for legal things like buying bitcoins. Advising someone to avoid certain things that are legal but also red flags, to avoid unnecessary discussions or account closures, is also not illegal.
In such a world, no bank could do business with another, since anyone could be arrested anytime for someone else's mistakes.
Funny how America complains to Russia about cases like Chodorkowski, but use the same twisted logic themselves all the time

Now all Bharara needs to do, is attack Mtgox for trading with Bitinstant and, of course, all banks that have done business with Mtgox. Finally troops have to be sent to Japan because the Japanese central bank has "knowingly" sent funds to these banks, "making good profits along the way". Perhaps there are some intermediary banks to attack as well? What a huge pile of crap.
Let's see how this develops.