&gt;It&#x27;s impossible to track bitcoin laundering when people transfer in and out of other currencies, between bitcoin addresses.<p>&gt;The process is called tumbling, and it&#x27;s primarily how bitcoin tax evaders use it now to get around the &quot;public&quot; ledger.<p>I very briefly addressed this at the bottom of my comment.<p>In short order:<p>- Tumbling is traceable: throw a beefy server at the list of transactions, and since you know how much money arrived in someone&#x27;s possession on a given date, you can now trace it backwards by crunching the numbers. Analysing long lists of transactions like this is something computers are <i>really</i> good at.<p>- But that doesn&#x27;t matter, because tumbling sites <i>can&#x27;t</i> work: they don&#x27;t have enough capital in them to successfully launder more than a few play dollars at a time.