Is Mixer illegal? Chainalysis believes that it is not illegal in itself, but in the United States, Mixer is obliged to register with FinCEN and implement anti-money laundering and other rules because it is a remitter. The implication is that it should not be illegal for ordinary users and can improve privacy, but criminals are likely to use these normal capital flows to increase their anonymity, which may bring unknowable risks to users’ own funds.