Dealing with crime in cryptocurrency based economies

Question

Most cryptocurrencies are anonymous where the origin of coins is not known and transactions are also anonymous (this may not be 100% true but lets assume perfect anonymity). The society prevents criminalization (using the coin to commit or pay for crime) of cryptocurrencies by forcing the exchanges that trade crypto for fiat to adhere to Anti Money Laundering (AML) rules.

However this assumes that the criminal wants to convert to fiat currency. But what if there is sufficiently big economy for the currency (sufficiently big market, businesses accepting the cryptocurrency etc.), and the criminal can live without the need of fiat money? Can the society prevent this behavior somehow other than outlaw cryptocurrencies?

The only solution I can see is to request the use of governmentally issued electronic signatures to sign all transactions which would allow pseudonymity in a way that one would be identifiable to the government but not to the ordinary public crowd.

Answer 1

Blockchain-based cryptocurrencies like Bitcoin aren't actually that untraceable, because the transfer history of every wallet is public. When cryptocurrencies ever become economically relevant, you can expect law enforcement to put all those currently hyped big data analysis and machine learning technologies to use and data-mine the blockchains for suspicious transactions. If you can then link a person to their wallet, you have proof that they initiated or received those transactions.

And making that link might not actually be that hard. First, we got usual instruments of police procedure like ip traffic surveillance, seizing the devices of suspects, etc.. And then it might be hard in a cryptocurrency-based economy to do many kinds of business without ever revealing your identity to the receiver of a payment. Order something online? Pay your rent? Your physical address is now linked to your wallet. Pay for something which requires a permit or age verification? Your name and face biometry is now linked to your wallet. Have a job with social security benefits? Pay your taxes? You just handed the link to the government without them even having to issue a warrant.

There are of course ways to "launder" cryptocurrencies, for example by sending them through a cryptocurrency tumbler service. But these are equivalent to the money laundering schemes we already have with traditional currency and we can expect that they will be suppressed the same way. So if the wallet you use to receive your salary and pay your taxes has transactions with known cryptocurrency laundering services, then you will likely get into trouble. Just like you will get into trouble in the present world if you regularly show up with a plastic bag full of banknotes at your local bank and try to deposit them without having a good explanation how you obtained them.

Answer 2

I imagine the future to be filled with government backed cryptocurrencies, where trade in one country is only with their own government-backed flavor. In this future hypothetical situation, the government would know when, where, how much was transferred and spent at all times.

Blockchain currencies like Ethereum already support and encourage new currencies to build on top of their blockchain 'api'

Answer 3

I think that Philipp's answer is not accurate enough. Even in cryptocurrencies that are pseudonymous and provide the least anonymity (like bitcoin) you can use your wallet's address only once in a transaction. This tears the link between multiple transactions. If you delete the private keys for your spend transactions no one can prove that you actually spent that money (in transactions that are historically linked to your current unspent money).

The situation then looks like this: your employer pays you salary from their address A to your newly created address B. You then buy something with B and pay to newly created address C and return your change to your new address D. This procedure repeats over and over again. If you are careful and spend your change in a given branch completely without merging it with your other branch (as a transaction input for bigger payment) then the money from that branch basically disappears and no one is able to connect it to the money in your other branches.

By branching I mean to ask for your income to be split right at the beginning - your employer pays your monthly salary to your 10 newly created addresses. Things get a bit more complicated like this.

For further reading regarding bitcoin address reuse you can see following:

• Address reuse at bitcoin wiki

• Is it safe to reuse a Bitcoin address? at Bitcoin SE

Cryptos whose goal is anonymity bring you then to a whole new level. With Monero the transactions are completely unlinkable for a blockchain observer and the ammounts are hidden too. See here for details.

Answer 4

Banknotes and coins are effectively untraceable, and other forms of pseudocurrency such as prepaid credit cards and Amazon gift cards have similar problems. Similar issues are found when buying and selling high-value items such as cars, gold, jewelry.

Nonetheless it's still possible to monitor transactions through various methods.

1. Business accounts. Businesses are required to keep accounts of all their incomings and outgoings. In many cases they are required to file these publicly. They are also used for taxation purposes, so the government has a powerful interest in ensuring their completeness. If a transaction is logged in an accountancy ledger, there is a record of it regardless how it is paid. Many criminal organisations have been exposed by people revealing their secret accounts.

2. Physical objects. You bought a car, you have a car. In many cases it is necessary to provide a delivery address to receive the physical object. Most objects are uniquely identifiable e.g. by serial numbers, unique IDs in electronic devices (mobile phones, computer CPUs, any network hardware with a MAC address...), chassis numbers on cars...

3. Additional legal requirements. Money-laundering regulations require every instance of certain types of transaction to be registered. Whether you're selling scrap metal, second-hand goods, or many other things that authorities want to track, you may be required to show ID and have that recorded. Property and car sales are usually recorded. These can be verified by other methods listed, but also simply by making test purchases.

4. Surveillance. It's relatively trivial to track people using CCTV, ANPR, WiFi, cellphones, etc.

5. Protecting participants' rights. If you buy a washing machine, you need some kind of proof of purchase to claim on a warranty. If you sell something taxable (property, car, inventory), you don't want to keep paying tax on it. Hence, in many cases purchases will be voluntarily recorded by one or other participant.

Answer 5

Since this is a bit of a more opinion based question I’ll add my two cents:

I think future cryptocurrencies will include systems of justice directly within their functionality.

Implementation matters, of course, but given that it’s possible to implement systems of justice in physical space, digital space will likely be possible, and offer all kinds of additional opportunities.