Michael Flynn told Mueller people connected to Trump admin or Congress attempted to influence him

Flynn, President Donald Trump's one-time national security adviser, gave Mueller a voicemail recording of one of the conversations. A federal judge has ordered that the voicemail's transcript, transcripts of Flynn's calls with Russian officials and potentially redacted parts of the Mueller report related to Flynn be made public, setting up the likelihood that even more details will be made public in the coming weeks.

The communications, from "persons connected to the Administration or Congress," Mueller wrote, "could have affected both (Flynn's) willingness to cooperate and the completeness of that cooperation."

"In some of those instances, the (Special Counsel's Office) was unaware of the outreach until being alerted to it" by Flynn, the newly unsealed court record from the Justice Department said.

The revelations raise the possibility that others around the President may have attempted to obstruct justice with the outreach to Flynn. However, Mueller, in both the Flynn court filing and his final report, did not go into detail on that possibility.

The voicemail

A voicemail from a Trump contact came the same night Flynn's lawyers told attorneys for Trump and the White House that they could no longer talk. It was days before Flynn pleaded guilty to a felony and formally agreed to cooperate with Mueller.

"It wouldn't surprise me if you've gone on to make a deal with ... the government. ... (I)f ... there's information that implicates the President, then we've got a national security issue, ... so you know, .... we need some kind of heads up," Trump's personal attorney said to Flynn's attorney in the voicemail, Mueller wrote in his final report in March. At least one of Flynn's lawyers later became a witness on his own in the investigation, speaking to Mueller about the contact, the special counsel's report noted.

Mueller determined that the voicemail could have obstructed the investigation but did not know if Trump himself had prompted the call.

"That sequence of events could have had the potential to affect Flynn's decision to cooperate, as well as the extent of that cooperation. Because of privilege issues, however, we could not determine whether the President was personally involved in or knew about the specific message his counsel delivered to Flynn's counsel," Mueller wrote in his report.

In all, the Flynn court records revealed Thursday show that the fired first national security adviser helped Mueller's investigation on at least three prongs: as the special counsel looked into interaction between the Trump transition team and Russia, WikiLeaks' release of emails during the presidential campaign and the President's efforts to interfere with the investigation. Flynn also assisted the Eastern District of Virginia and prosecutors from the Justice Department's National Security Division with a now-open case against his former lobbying partner, who allegedly worked illegally for Turkey.

A description of another topic of Flynn's cooperation is still blacked out in the court record.

Flynn pleaded guilty in December 2017 to lying to the FBI in the first days of the Trump White House about his interactions with then-Russian Ambassador Sergey Kislyak and about his lobbying for Turkey. Flynn has not yet been sentenced, partly because the lobbying case in Virginia is still ongoing, and he may testify at that trial.

In Mueller's obstruction probe, the special counsel found evidence that Trump had taken steps to obstruct the Russia investigation and had reason to want to thwart Mueller's efforts. But Mueller declined to decide whether the President should be charged with a crime. Attorney General William Barr and then-Deputy Attorney General Rod Rosenstein chose not to charge Trump.

Mueller charged several former Trump advisers in addition to Flynn with lying or witness tampering.

The Justice Department said Tuesday that confidential parts of Flynn's court record could be made public now because the Mueller report is out.

By the end of this month, the department will have to release transcripts of the voicemail, Flynn's calls with Kislyak and potentially other Russian officials, and parts of the Mueller report pertaining to Flynn that may still be redacted, the judge overseeing Flynn's case, Emmet Sullivan of the US District Court in DC, ordered Thursday.

WikiLeaks and transition help

Other documents revealed Thursday show that Flynn was among "a select few people" who heard statements among campaign officials about WikiLeaks and spoke to Mueller about those conversations. That included a discussion by unnamed campaign officials of reaching out to WikiLeaks after it had released emails the Russians had stolen from the Clinton campaign.

"The defendant relayed to the government statements made in 2016 by senior campaign officials about WikiLeaks to which only a select few people were privy. For example, the defendant recalled conversations with senior campaign officials after the release of the Podesta emails, during which the prospect of reaching out to WikiLeaks was discussed," according to the newly unredacted documents.

It was not known previously how much Flynn had contributed to this part of the investigation, as much of the Mueller report related to WikiLeaks is still redacted because of the ongoing case against Roger Stone or other unnamed ongoing investigations.

Mueller's final report had made clear that Flynn contributed to the probe into the presidential transition and possible obstruction of justice by the President.

The newly unsealed parts of Flynn's case also highlight how important it was that he became an early, well-known cooperator with Mueller.

"In some instances, individuals whom the (Special Counsel's Office) interviewed before the defendant's guilty plea provided additional, relevant details about their knowledge of key events after his cooperation became public," Mueller wrote, according to another page of the court record unsealed on Thursday.

This story has been updated.