George Papadopoulos guilty plea shows Donald Trump Jr. may be incredibly vulnerable

George Papadopoulos pleaded guilty to lying to investigators about a Russian offer of "dirt" on Hillary Clinton remarkably similar to one made to Donald Trump Jr. -- who may face new legal jeopardy in the special counsel probe.

The 30-year-old Papadopoulos officially joined the Trump campaign's foreign policy advisory board March 21, 2016, and just three days later was contacted by a woman he believed had connections to "high-level Russian government officials," according to his plea.

The Russian contact promised damaging information about Clinton that came from hacked and stolen emails, but Papadopoulos told FBI agents he met the woman before joining the campaign and brought knowledge of the hacked data with him.

However, special counsel Robert Mueller's investigators found evidence the contacts came only after joining the Trump campaign, and Papadopoulos was arrested July 27 -- one day after FBI agents raided Paul Manafort's home -- and began cooperating with the probe.

There's nothing in the guilty plea to directly implicate the president's son, who set up a June 9, 2016, meeting with a Russian attorney promising "dirt" on Clinton -- but the court documents show a much clearer picture of what investigators already know.

Court documents show investigators have known or strongly suspected since late January that Russians had promised campaign assistance through Papadopoulos since at least late April 2016, and he then lied about it.

The documents refer multiple times to Papadopoulos keeping “high level campaign officials” notified of his efforts to set up meetings between Russia, including President Vladimir Putin, and the Trump campaign, including Donald Trump.

One of those email notifications was sent June 1, 2016, by Papadopoulos to a "high-ranking campaign official" who referred him to the "campaign supervisor" who was "running point."

Carter Page, who served on the same advisory committee as Papadopoulos, traveled to Moscow in July 2016 with the permission of former campaign manager Corey Lewandowski, but without the blessing of his campaign supervisor, J.D. Gordon.

An associate emailed Trump Jr. on June 3, 2016, to set up a meeting with the "Russian government lawyer" to discuss the campaign, and the president's son invited Manafort -- one of the campaign officials described in the plea -- and his brother-in-law Jared Kushner.

The guilty plea signed by Papadopoulos, who has turned over documents to the special counsel and likely has worn a wire, show it's nearly impossible that Manafort -- and possibly Trump Jr. and Kushner -- did not know what the meeting would be about.

Trump Jr. later offered shifting explanations of the meeting, which Mueller's team is investigating as possible obstruction of justice by the president himself.

Trump personally dictated the first, demonstrably false statement while flying home from the G-20 meeting where he met privately with Putin.

According to court documents, Papadopoulos told Trump on March 31, 2016, about his efforts to set up a meeting during the campaign between Trump and Putin, and he continued trying to arrange a meeting with Russian officials, with the campaign's knowledge, until at least August 2016.

Although individual campaign officials and associates are not identified in the plea agreement, Mueller's team clearly knows who they are, and some of them may have been recorded by Papadopoulos after his unpublicized arrest three months ago.

News reports published Aug. 14 revealed Papadopoulos had sent at least a half-dozen requests for Trump or campaign associates to meet with Russian officials, but those failed to attract sustained attention.

Trump Jr. was interviewed Sept. 7 by congressional investigators, one of whom suggested in a tweet that the president's son had broken the law by lying.

It's not clear what Sen. Chris Coons (D-DE) believes Trump Jr. may have lied about, but investigators frequently ask questions to which they know the answers to gauge their target's truthfulness.

According to news reports, Trump Jr. told the Senate Judiciary Committee that he didn't inform his father of the meeting -- but the Papadopoulos plea shows nearly everyone around the candidate were aware of Russian efforts to deliver damaging information on Clinton.

Rob Goldstone, who pitched the Trump Tower meeting and also attended it, said it would be “part of Russia and its government’s support for Mr. Trump" of which Papadopoulos was a part -- and which he just pleaded guilty to lying about.