‘Staggering’ Crypto Seizures Have Cops Struggling to Keep Up

One spring day in a village just west of London, residents saw a man being muscled into a car in front of a nearby house. He reappeared with cuts and bruises 13 hours later, but the cops had already discovered the house was a cannabis-growing operation. A separate search of the man’s home in a nearby town turned up something more intriguing—some of the first cryptocurrency that would ever be seized by U.K. police.

That era-defining 2017 case yielded a safety-deposit box containing jewelry, gold bars, £263,000 ($345,000) in cash, and an item that flummoxed the lead investigator, Matthew Durkin, a 19-year veteran of the Surrey police. It was a USB device found in the suspect’s study. The gadget was wrapped in a small notebook, which contained two strings of 12 random words. A young probationary officer recognized the device, a KeepKey, as a virtual currency holder and the words as seed phrases to access crypto wallets. Eventually, police discovered it held 295 Bitcoin.

“It meant nothing to me until someone said it was worth £900,000,” recalls Durkin, 51.

In recent years, police departments such as Durkin’s and law enforcement agencies around the world have had to learn quickly about how to deal with crypto­currencies, often in amounts that eclipse traditional assets such as cash, gold, jewelry, cars, and real estate. In London, for instance, police seized almost £300 million of crypto linked to crime last year.

The U.S. Marshals Service held 22 cryptocurrencies valued at about $919 million last December, according to spokeswoman Shaunteh Kelly. In February the U.S. made its largest financial seizure ever: about $3.6 billion in Bitcoin stolen during a 2016 hack of the Bitfinex currency exchange. And cryptocurrencies made up almost all—93%—of the assets confiscated by the Internal Revenue Service’s Criminal Investigation Division in the fiscal year that ended Sept. 30.