# Vitalik: Railgun's privacy pool mechanism for ethical crypto transactions

Source: https://x.com/VitalikButerin/status/1889995280524681393
Kiwi News: https://news.kiwistand.com/stories/Vitalik-Railguns-privacy-pool-mechanism-for-ethical-crypto-transactions?index=0x67ade2635e3add56a3c704c8083f3c78dfbbf19e770eee7ce3f67b68c76554b2e89beccf
Submitted by tim on 2025-02-13 UTC, 1 upvote, 0 comments

## Summary

Vitalik Buterin highlights Railgun's privacy pools mechanism as a working way for the protocol to avoid serving proceeds of crime without using snooping or backdoors. Deposits go through an automated filter during a one-hour period that checks whether they likely came from criminal activity. Deposits that pass can be withdrawn privately with zero-knowledge proofs after one hour, though waiting longer is recommended for a larger anonymity set. Deposits that fail can only be withdrawn to the depositor's own address, with no risk of freezing or seizure, but without access to the privacy pool.

## Article

This is a solid demonstration of Railgun's privacy pools mechanism ( https://papers.ssrn.com/sol3/papers.cfm?abstract_id=4563364 ) working in practice, allowing Railgun to avoid serving proceeds of crime without using any snooping / backdoors.

How it works:

* Anyone can deposit into Railgun.
* After you deposit, there is a 1 hour period during which various algorithms detect whether or not the deposit likely came from what the algorithms consider to be criminal activity.
* If your deposit passes the filter, then after 1 hour you can use ZKPs to withdraw privately (but ideally wait longer to get a good-enough anonymity set).
* If your deposit fails the filter, then you can only withdraw back to your own address. There is no risk that your funds will get frozen/seized, you just can't benefit from the privacy pool.

If you disagree with Railgun's filters, anyone is free to fork and make their own pool with their own rules, though if you can't get reasonably wide public support you're going to have a tiny anonymity set.

https://www.railway.xyz/