(CN) - A former foreign-policy adviser to President Donald Trump's 2016 campaign secretly pleaded guilty earlier this month to lying to the FBI about his contacts with Russian officials, court documents unsealed Monday show.
George Papadopoulos was charged with lying to FBI agent in July and entered the guilty plea in a closed courtroom in Washington on Oct. 5.
Unlike the indictments against Trump campaign chairman Paul Manafort and business associate Rick Gates also announced by special counsel Robert Mueller's office on Monday -- charged related to activities outside of the Trump campaign -- the single felony count against Papadopoulos is directly related to the 2016 election.
Papadopoulos was reportedly seeking information on Democratic presidential nominee Hillary Clinton's missing emails from her tenure as secretary of state, an issue candidate Trump repeatedly brought up on the campaign trail.
Papadopoulos, who joined the Trump campaign as a foreign-policy adviser in March 2016, admitted to lying to the FBI in January about his contacts with an unidentified Russian professor and a representative of the Russian Ministry of Foreign Affairs. Mueller took over the probe as special counsel in May after Trump fired former FBI Director Richard Comey.
Mark Zaid, a Washington D.C. attorney who often focuses on government accountability issues, said, “Papadopoulos brings this case even closer to the Trump inner circle. His actions raises serious questions about why Papadopoulos felt it necessary to lie to the FBI about campaign matters relating to Russia. This opens the door to direct connections.”
According to court documents, Papadopoulos was in communications with a Russian professor who contacted the Trump campaign in April 2016. The professor claimed that Russian officials had access to thousands of emails he said would embarrass Clinton and damage her campaign.
"The Professor claimed to have substantial connections with Russian government officials, which defendant Papadopoulos thought could increase his importance as a policy advisor to the Campaign," the documents say.
Papadopoulos allegedly met with the unnamed professor in London on March 24, 2016 who brought with him someone introduced as "a relative of Russian President Vladimir Putin with connections to senior Russian government officials."
The Russian ambassador in London is also believed to have been present.
After he met the professor in London, Papadopoulos emailed Trump campaign officials and told them during the meeting they discussed arranging another meeting between the campaign and Russian officials "to discuss U.S.-Russia ties under President Trump."
The statement says, "the Campaign Supervisor responded that he would 'work it through the campaign,' but that no commitments should be made at that point. The Campaign Supervisor added: 'Great work.'"
During another meeting Papadopoulos had with the anonymous professor in London on April 26, 2016, the professor said he had just returned from meeting with high-level Russian government officials in Moscow and learned the Russians "had obtained 'dirt' on then-candidate Clinton.'"
He later told the FBI: "They [the Russians] have dirt on her; the Russians had emails of Clinton; they have thousands of emails."
"Have been receiving a lot of calls over the last month about Putin wanting to host him and the team when the time is right," Papadopoulos wrote to a high-ranking Trump official.
In mid-August, the Trump campaign supervisor told Papadopoulos: "I would encourage you" and another foreign policy advisor to the campaign to "make the trip, if it is feasible."
Papadopoulos admitted he repeatedly tried to arrange a meeting with Russian government officials and a women he believed to be the niece of Russian President Vladimir Putin, but that his efforts were unsuccessful.
He is not the only former foreign policy adviser to Trump to come under scrutiny. Carter Page, who joined the campaign the same month as Papadopoulos, has been questioned by the FBI about his own meetings with Russians.
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