Speaking to the BBC, Europol director Rob Wainwright said the agency estimated $137.5 billion in illicit currency is circulating through Europe — and 4 percent of it was being exchanged via cryptocurrencies like bitcoin.
Crypto transactions are untraceable, making it far more difficult for police to combat these transfers. "[Cryptocurrencies] are not banks and [thus] governed by a central authority, so the police cannot monitor those transactions," Wainwright said. "And if they do identify them as criminal they have no way to freeze the assets, unlike in the regular banking system."
The EU has passed laws to counteract bitcoin's anonymity. All bitcoin purchases require a "fingerprint" that attaches a name to the transaction — but the same is not true of bitcoin transfers. Police may be able to find out where the money came from, but not where it went.
"It's very difficult for the police in most cases to identify who is cashing this out. They have to take a responsible action and collaborate with us when we are investigating very large-scale crime. I think they also have to develop a better sense of responsibility around how they're running virtual currency," Wainwright said.
Other cryptocurrencies, such as Monero and Zcash, prove an even harder challenge: they both use randomized algorithms that make both the source and destination of purchases almost untraceable. Wainwright added that more and more criminals are switching to these alternative cryptocurrencies for that very reason.
Criminals accept cryptocurrency payment for drugs, then cash the cryptocurrency out for clean, traditional money.
Wainwright called on crypto developers to coordinate with police more and "develop a better sense of responsibility" as their open-source currency increases in political and economic relevance with every passing day.
Bitcoin exploded in 2017 from about $1,000 per coin at the beginning of the year to almost $20,000 at its peak in December. The value has contracted rapidly since then and sits at about $8,500 at the time of this writing.
On Sunday, it was revealed that BrowseAloud, a plugin meant to make websites more readable to visually impaired people, was a mule for a hijacking program that converts computers visiting certain websites into cryptocurrency miners, using electricity drawn by the computer to facilitate bitcoin generation. Among the infected websites included some used by the British government.
And earlier in February, a Welsh drug dealer was sentenced to eight years in prison when he was found guilty of operating a dark web pharmacy that sold the highly addictive opioid fentanyl. His shop exclusively accepted bitcoin transactions.