It's way easier to correlate activity to a particular person with a blockchain than with traditional banking. There are no administrative hoops to getting access to transaction data.
Anything you tumble, you can (provably) de-tumble. It's just expensive and time-consuming (re-building the blockchain state, yadda yadda). Crypto banking is less anonymous than actual banking, especially if you actually want to pull your money into fiat and need to go through an exchange.
One-sided JM for BTC include Wasabi and Samourai Whirlpool. Though Samourai are a bit sketch IMO.
not really? If you have a transaction that has five equally sized inputs A_{1...5} and five equally sized outputs B_{1...5}, then the max extent you can "provably" de-tumble B_1 is saying "there's a 20% chance that it came from A_1, 20% chance it came from A_2, ..."
You can't do this[1], as the blockchain does its best to be perfectly deterministic. Best you can do is get an oracle to get you a random seed (which you'll see publicly in the oracle token), so you'll know exactly "what went where."
[1] https://blog.chain.link/random-number-generation-solidity/
Doesn’t it just need to require that the sum of the inputs is equal to the sum of the outputs?
The transaction chains are generally constructed off-chain.
For Ethereum you can do fancier things with zk constructs, like Aztec and Tornado Cash.
Source? Enough CoinJoins (Wasabi+Joinmarket) and I don’t think so. Note CJ work a bit different than the oldschool custodial tumblers. Combining CJs with LN (reverse) submarine swap for another layer.
With large enough anyonymity sets you should have plausible deniability. This is also a bit time-consuming, more so the larger the amount; there’s no way to do a complete end-to-end transaction of billions of dollars untracably in mere hours without standing out I think. But if you have days/weeks to break the link I think it’s def doable and done.
Obviously make one single mistake and you’re out, but that’s in the nature of these things.
If I’m wrong I’d very much appreciate something substantial.
I don't really know, but putting myself in a criminal's shoes, I don't like the idea that my transactions stay in plain view forever. It makes statistical attacks very, very easy. It also makes me vulnerable as-of-yet-undiscovered statistical attacks.
BitCoin is arguably the worst thing for organized crime.
We will soon be living in a world where crime is the norm.
Why do you believe tornado to be secure? The project is self described as experimental software.
“ Tornado.cash was audited. However, it is still an experimental software. Please use at your own risk.”
Some people will say they aren’t doing anything big enough to warrant attention but that’s forgetting that everyone using a tumbler is paying extra to help anonymous strangers launder money. If anyone involved attracts attention it’ll bring scrutiny to everyone else, and potentially the need to prove that you were “just” committing a small-scale crime and didn’t know that most of the other coins being tumbled belonged to a cartel.