Michael Cohen, the former lawyer to Donald Trump who once said he’d take a bullet for the president, has been given a 36-month prison sentence.
He is the first member of Mr Trump’s inner circle to be jailed over the special counsel’s inquiry into alleged Russian meddling in the 2016 election.
He has pleaded guilty to crimes including campaign finance violations, tax evasion and lying to Congress.
In a New York court on Wednesday Cohen lashed out at his former boss.
The 52-year-old told Judge William Pauley that Mr Trump caused him to “follow a path of darkness rather than light”.
He told the court his “weakness was a blind loyalty to Donald Trump” and that he “felt it was my duty to cover up his dirty deeds”.
The sentencing was related to two separate cases brought by the Southern District of New York and Special Counsel Robert Mueller’s Russia investigation.
Mr Cohen pleaded guilty to campaign finance violations for his role in making hush money payments to women who alleged affairs with Mr Trump.
He will serve that term concurrently with a two-month sentence he was given for lying to Congress about a possible Trump Tower project in Moscow, a charge levelled by Special Counsel Mueller.
The judge gave Cohen until 6 March to report to jail at the Otisville prison in upstate New York.
In addition the jail term, he was also ordered to forfeit nearly $2m (£1.6m).
As he left the court, he did not pause to speak to the assembled media.
A decade of ‘misfortune’
Anthony Zurcher, BBC News, Washington
If there’s a lesson to be learned from the tale of the two Michaels, it’s that deals with federal prosecutors are best done quickly.
Former Trump national security adviser Michael Flynn, when confronted by the special counsel’s office, was quick to co-operate. He may end up with a sentence that includes no jail time.
Michael Cohen, on the other hand, initially put up a legal fight. Prosecutors say he never fully co-operated. Now the 52-year-old is facing three years in prison.
Another message from the fate of the two Trump associates is that Mr Trump’s business dealings, not Russian election meddling, could present a greater legal threat to the president. According to Mr Cohen’s lawyer, his client had the “misfortune” of being the president’s personal lawyer, business partner and all-around fixer for more than a decade. When investigators began digging into his actions, they uncovered a variety of chargeable crimes.
By all accounts, Mr Trump’s larger business empire is getting similar scrutiny. His long-time accountant is co-operating with investigators.
There’s no telling where Mr Mueller’s Russia investigation will end up, but one thing is clear – it’s not the only shark circling the White House.