By lying to investigators, Papadopoulos had made "a calculated exercise of self-interest over the national interest", said Moss.
Hours after George Papadopoulos (an ex policy advisor to Trump) was sentenced to two weeks in jail for lying to FBI investigators, a court heard that the Maltese professor he met with to connect him with Russian officials may be dead.
Memos authored by House Republicans and Democrats, now declassified, show that information about Papadopoulos' contacts with Russian intermediaries triggered the FBI's counterintelligence investigation in July 2016 into potential coordination between Russia and the Trump campaign.
While the President had belittled Papadopoulos following his guilty plea last yea, calling him a "low level volunteer", he was actually one of just five foreign policy advisers for Mr. Trump during his 2016 presidential campaign. He hasn't returned since.
"I made a bad mistake for which I paid dearly and I am terribly ashamed", Papadopoulos said in court.
"I hope to have a second chance to redeem myself", Papadopoulos told the judge.
Thomas Breen, Papadopoulos's lawyer, admitted that his client had been "naive" and "a fool", but he also cast blame on President Trump.
CNN's Tapper noted that Session's attorneys said that Sessions stands by his testimony, and denied encouraging a meeting with Russians.
Russian Federation has denied USA allegations that it interfered in the campaign, while Trump has regularly lashed out against the sprawling probe he dubs a "witch hunt" driven by his Democratic foes. A spokeswoman for Sessions declined to comment after Papadopoulos's filing last week. He has been sentenced to 14 days in prison, plus a year of supervision and 200 additional hours of community service.
"The sentence imposed here should reflect the fact that lying to federal investigators has real consequences, especially where the defendant lied to investigators about critical facts, in an investigation of national importance, after having been explicitly warned that lying to the FBI was a federal offense", the prosecutors added.
"I made a terrible mistake, but I am a good man who is eager for redemption", Papadopoulos said at his sentencing hearing.
The FBI met with Mifsud while he was visiting the United States in early 2017, but Papadopoulos' lies "undermined investigators' ability to challenge the professor or potentially detain or arrest him".
Moss noted that many similar cases resulted in probation but said he imposed a sentence of incarceration partly to send a message to the public that they can't lie to the Federal Bureau of Investigation. Lawyers for Papadopoulos had appealed for probation.
Prosecutors say Mifsud arranged a meeting in London cafe between Papadopoulos and a young woman he falsely described as Russian President Vladimir Putin's niece. However, they wrote, the claim that his lies harmed the investigation are "speculative and contrary to the evidence".