Roger J. Stone Jr, the Republican political consultant who for years portrayed himself as the dirty trickster of American politics, was sentenced on Thursday to more than three years prison for obstructing a congressional inquiry in a bid to protect President Trump.

The case against Stone, 67, a longtime friend of Trump’s, had become a cause célèbre among the President’s supporters. Trump has attacked the prosecutors, the jury forewoman and the federal judge overseeing the trial, casting his former campaign adviser as the victim of a vendetta by law enforcement.

Stone was convicted of lying to congressional investigators and trying to block the testimony of a witness who would have exposed his lies to the House Intelligence Committee. At the time, the panel was investigating whether Trump’s campaign conspired with the Russian government to influence the 2016 presidential election.

Judge Amy Berman Jackson said that for months, Stone carried out a deliberate and calculated effort to hinder an important congressional inquiry by blatantly lying, hiding hundreds of documents and pressuring a fragile witness. Stone enjoys “mind-games” and political gamesmanship, she said, but “nothing about this case was a joke. It wasn’t a stunt and it wasn’t a prank”.

She added, “He was not prosecuted to give anyone a political advantage. He was not prosecuted, as some have complained, for standing up for the President. He was prosecuted for covering up for the President.”

Handing down a 40-month sentence, Judge Jackson said Stone’s behaviour inspired “dismay and disgust”.

His sentencing played out amid extraordinary upheaval at the justice department and a standoff between the President and attorney-general William P. Barr over Trump’s comments about the case.

The President has criticised the jury’s verdict, claiming that “the real crimes were on the other side”. He intensified those attacks last week after the prosecutors recommended that Stone be sentenced to seven to nine years in prison.