Tornado Cash runs within the Ethereum network and is also secured by zero-knowledge proofs. The Tornado Cash protocol and the anonymity mining protocol has long been audited by quite a few professional audit firms which include Zeropool. “With Tornado Cash, the defendant developed a shortcut for funding crimes and terrorism,” https://cruisenewser.com/how-tornado-cash-enhances-privacy-for-ethereum-and-bnb-transactions/