As far as I know, criminals are now using bitcoin to wash money. A recent study from a financial agency that monitors and imposes US economic sanctions - U.S. The Center for Sanction and Illicit Finance, the FDD and Blockchain Elliptic, have uncovered a "Bitcoin Money Laundering" ecosystem. Elliptic's Legal Analysis of Bitcoin Blockchain and publicly available data are used to track illegal funds from 2013 to 2016.
"This study aims to find where individuals withdrew or transferred Bitcoin (BTC) from illegal agencies and to identify the types of money laundering," the report said.