NEW YORK — William “Bill” Hill, 67, one of the co-founders of Bitcoin mixer Samourai Wallet, was sentenced to four years in prison on Wednesday for his role in creating the privacy tool prosecutors say was used to launder at least $237 million in criminal proceeds.

District Judge Denise Cote of the Southern District of New York (SDNY), who recently sentenced Hill’s fellow Samourai Wallet developer Keonne Rodriguez to the statutory maximum of five years in prison for the same crime — conspiracy to operate an unlicensed money transmitting business, which both men pleaded guilty to in July — said she was “varying” Hill’s sentence due to several mitigating factors, including Hill’s recent autism diagnosis and his advanced age.

“I accept that it will be a more difficult time for the defendant to be in prison than many other people,” Cote said. “I would be imposing a sentence of 60 months otherwise.”

Hill’s lawyer, Roger Burlingame of Dechert LLP, spent a considerable portion of Wednesday’s hearing detailing how Hill’s autism was the explanation — or, as Burlingame put it, “the key that unlocks the riddle” — for Hill’s conduct.

Bitcoin, Burlingame said, was “like catnip” to a black-and-white thinker like Hill, who was attracted to the “idealism and absolutism” of blockchain technology, the “noble purpose…of fending off an encroaching government, an Orwellian dystopia,” and a built-in community of fellow bitcoin enthusiasts — something he said Hill “never had before in his entire life.”

Hill’s lawyer also said that his autism explained why he thought what he was doing with Samourai Wallet was legal. Because the Financial Crimes Enforcement Network (FinCEN) did not require non-custodial wallets to register as money transmitting businesses, Burlingame said Hill acted as if he had a “forcefield” around his actions, adding that Hill had come to see this as a “pathetically naive view...a magical-thinking, autistic view of the world.”

Burlingame asked that Hill be sentenced to time served, adding that his three-month stint in a Portuguese prison last year was punishment enough to deter him from ever breaking the law again.

“Jail is extraordinarily hard for him given his extreme sensitivity,” Burlingame said, adding that the forced socialization of being in prison is “torture” to Hill.

As Burlingame spoke, Cote interjected several times to ask whether Hill understood that what he had done was morally wrong, not just illegal.

“There’s a way of arguing that no law was violated — that’s just not true,” Cote said. “I reject entirely that the defendant doesn’t know the difference between right and wrong, or that his autism prevented him from living a moral life.”

When it was Hill’s turn to address the judge, he was visibly emotional as he spoke about the negative impact his prosecution had had on his wife, Sabrina, and his extended family.

“I told myself that my work was about [freedom] but in truth, I was rationalizing my own hubris,” Hill said. “I have learned a painful but essential lesson from this experience and I take full responsibility for my actions.”

In addition to the sentence of 48 months in prison, Cote sentenced Hill to a period of three years’ supervised release, which he will be allowed to serve from Lisbon, where he lives with his wife, plus a fine of $250,000. Cote said that she will recommend that Hill receive credit for the time he served in Portugal before he was extradited to the United States, potentially shaving 11 weeks off his remaining sentence.

Hill must self-surrender to begin his sentence by Jan. 2, 2026.