Here’s who (probably) did that massive $150,000,000 Bitcoin transaction (washingtonpost.com)
From the article: "Who was responsible for the transaction? I asked Sarah Meiklejohn, a computer scientist at the University of California, San Diego, for her thoughts. She's the author of a recent paper demonstrating that sophisticated analysis can reveal a lot of information about who is responsible for Bitcoin transactions. She has combined a large database of Bitcoin addresses tagged with their likely owners."
Link to the paper is provided.
In other words, the only way you get to have the money is if you never spend it, except in minuscule amounts.
As Silk Road (and hundreds of years of cash-based money transfers) shows, the fact that BTC is hard to trace hardly makes laws unenforceable.