“What is happening today is not and cannot be a review and a revision by a sentence imposed by another court,” Judge Jackson said on Wednesday, referring to the sentence Mr. Manafort received last week.
Hanging over the entire case has been the chance that Mr. Trump could pardon Mr. Manafort. Asked about that possibility, Mr. Trump’s answers have varied. He said late last year that he “wouldn’t take it off the table.” More recently, he said, “I don’t even discuss it.”
Asked about a pardon on Monday, Sarah Huckabee Sanders, the White House press secretary, said, “The president has made his position on that clear, and he’ll make a decision when he is ready.”
Last June, when Judge Jackson revoked Mr. Manafort’s bail and sent him to jail after prosecutors filed new charges of witness tampering, President Trump said Mr. Manafort was being treated like a mafia boss.
“Who was treated worse, Alfonse Capone, legendary mob boss, killer and ‘Public Enemy Number One,’ or Paul Manafort, political operative & Reagan/Dole darling, now serving solitary confinement — although convicted of nothing?” Mr. Trump wrote on Twitter.
After the sentencing, Mr. Downing told reporters outside the courthouse that the judge had handed down a “callous, harsh sentence that is totally unnecessary.” Judge Jackson conceded that the prosecutors brought no evidence of a conspiracy with Russia’s election interference, he said, omitting that she also noted that the Kremlin’s campaign was never part of the Manafort case and she was not responsible for ruling on it.
Judge Jackson is comfortable with complex decisions, said Robert P. Trout, a defense lawyer who runs the law firm where she worked for a decade before President Barack Obama appointed her to the bench in 2011. “If anyone can get their head around the complexities and sensibilities of the sentencing considerations in play here, it is Judge Jackson,” Mr. Trout said.