Blockchain.info, aside from being a great tool and web wallet, offers and advertises a coin mixer service - or to put it in plain English, a money laundering service. Under what jurisdiction is money laundering legal??
Under any jurisdiction that doesn't have a law that makes what blockchain.info illegal. If there's a US Federal law that you think makes it illegal, I'd love a citation. Honestly, I don't know if it's legal or not. My bet is that you could probably find some law you could cram it into, but that's true of almost anything.