Michael Flynn left the Trump White House this week. Here's how that happened

Updated at 6:53 p.m. ET May 8, 2017

The events leading to Michael Flynn's resignation as national security adviser accelerated this week, with constant new updates about what he said, to whom and when. But the path to that step has been unfolding since at least last summer. Here's a timeline of key events that eventually led to the resignation of a top presidential adviser less than one month into the Trump administration.

June through November 2016 Early in the summer, the Washington Post reports that hackers in the Russian government have breached the Democratic National Committee. Sources from the DNC and security experts tell the Post that the hackers had access to opposition research on Trump, as well as internal emails and chats.

In late July, WikiLeaks posts a searchable database of more than 19,000 emails stolen from the DNC computer servers. Compromising information in the emails leads to the resignation of Debbie Wasserman Schultz as DNC chair.

Donald Trump, meanwhile, eggs the Russians on.

"Russia, if you're listening, I hope you're able to find the 30,000 emails that are missing," he says. Trump repeatedly downplays the hacks in the coming months, saying in a debate that China or "somebody sitting on their bed that weighs 400 pounds" could have been behind the breaches. Days after the U.S. intelligence community says it's "confident that the Russian Government directed the recent compromises of emails," Trump dismisses concerns about the breach.

"You ever notice anything that goes wrong, they blame Russia? 'Russia did it.' They have no idea," he says in a speech.

Nov. 8, 2016

Donald Trump wins the presidential election.

Nov. 10, 2016 President Obama warns President-elect Trump against Flynn during a meeting in the Oval Office, a former Obama official told NPR months after the tête-à-tête. Nov. 18, 2016 President-elect Trump announces that Flynn will be his national security adviser. Flynn, it is later reported, had been in contact with Russian Ambassador Sergey Kislyak before the election. Dec. 9, 2016 Then-President Obama orders a "full review" of digital attacks aimed at influencing U.S. elections, going back to 2008. The Washington Post reports that the CIA has determined that the Russian government was seeking to help Trump win the election. The Trump transition office issues a statement: "These are the same people that said Saddam Hussein had weapons of mass destruction," the statement says. "The election ended a long time ago in one of the biggest Electoral College victories in history. [Note: This is incorrect.] It's now time to move on and 'Make America Great Again.' " Dec. 12, 2016 Trump tweets: "Unless you catch 'hackers' in the act, it is very hard to determine who was doing the hacking. Why wasn't this brought up before election?" Dec. 15, 2016 Trump tweets, "If Russia, or some other entity, was hacking, why did the White House wait so long to act? Why did they only complain after Hillary lost?" Secretary of State John Kerry says on CNN that then-President Obama did issue a warning about Russian hacking, but he also "had to be obviously sensitive to not being viewed as interfering on behalf of a candidate or against a candidate or in a way that promoted unrealistic assessments about what was happening." Obama tells NPR's Steve Inskeep that the U.S. will strike back against Russia, one way or another, in response to that country's attempts to influence the U.S. election.

"I think there is no doubt that when any foreign government tries to impact the integrity of our elections, that we need to take action," he says. "And we will — at a time and place of our own choosing. Some of it may be explicit and publicized; some of it may not be."

He added, "But Mr. Putin is well aware of my feelings about this, because I spoke to him directly about it."

Dec. 25, 2016

Flynn and Kislyak exchange text messages wishing each other happy holidays (per remarks later made by Sean Spicer on Jan. 13, 2017).

Dec. 29, 2016 Obama ejects 35 Russian diplomats from the United States and introduces new sanctions against Russia's Federal Security Service, the FSB; the country's main foreign intelligence agency, known as the GRU; along with four GRU officers and three companies that did business with GRU.

In addition, the Obama administration announces it will be closing down two compounds in the U.S. it says were "used by Russian personnel for intelligence-related purposes."

Dec. 29 is also when the conversations between Flynn and Kislyak regarding sanctions took place (this story would break on Jan. 12, 2017). According to a Washington Post story from Feb. 9, two officials "said that Flynn urged Russia not to overreact to the penalties being imposed by President Barack Obama, making clear that the two sides would be in position to review the matter after Trump was sworn in as president." Jan. 6, 2017 The Office of the Director of National Intelligence releases a declassified report finding that Russian President Vladimir Putin ordered a campaign to influence the U.S. presidential election and that a major part of that was the hacking of emails at the Democratic National Committee.

"Putin and the Russian Government aspired to help President-elect Trump's election chances when possible by discrediting Secretary Clinton and publicly contrasting her unfavorably to him," the report says. The authors added that "Russia's goals were to undermine public faith in the U.S. democratic process."

Trump meets with intelligence officials for a briefing on the report's contents. Afterward, he releases a statement lumping Russia in with China and "other countries" and insisting that the hacking had "absolutely no effect" on the election's outcome:

"While Russia, China, other countries, outside groups and people are consistently trying to break through the cyber infrastructure of our governmental institutions, businesses and organizations including the Democrat National Committee, there was absolutely no effect on the outcome of the election including the fact that there was no tampering whatsoever with voting machines."

However, as then-Intelligence Director James Clapper had told John McCain just one day earlier, it's impossible to know the impact: "Certainly the intelligence community can't gauge the impact that it had on choices that the electorate made. There is no way for us to gauge that." Jan. 10, 2017 Then-Attorney General nominee (and Alabama Sen.) Jeff Sessions says in his confirmation hearing that he "has no reason to doubt" the report's conclusions tying Putin to the DNC hack. Jan. 11, 2017 In his confirmation hearing, then-Secretary of State nominee Rex Tillerson acknowledges that he thinks it's "a fair assumption" that Putin had knowledge of the plot to influence the U.S. election. He also adds that the intelligence report on Russian hacking "clearly is troubling." Jan. 12, 2017 The Washington Post's David Ignatius reports that "a senior U.S. government official, Flynn phoned Russian Ambassador Sergey Kislyak several times on Dec. 29," the same day that the Obama administration announced the new sanctions and removal of Russian diplomats. Jan. 13, 2017

White House press secretary Sean Spicer says that a conversation took place between Flynn and Kislyak, but that the conversation was on Dec. 28, and that it wasn't about sanctions.

He says that Kislyak texted Flynn on the 28th, asking if he could give Flynn a call. Kislyak then called that day, and according to Spicer, "the call centered around the logistics of setting up a call with the president of Russia and the president-elect after he was sworn in, and they exchanged logistical information on how to initiate and schedule that call. That was it, plain and simple." This proves to be untrue, as two Trump transition officials confirm to NPR that a call took place on Dec. 29. Jan. 15, 2017 Officials from the Justice Department and intelligence agencies discuss "whether the incoming Trump White House should be notified about the contents of the Flynn-Kislyak communications," as the Washington Post has reported. Later that day, on CBS's Face the Nation, Vice President Pence says the conversations between Flynn and Kislyak had nothing to do with sanctions.

"What I can confirm, having spoken to him about it, is that those conversations that happened to occur around the time that the United States took action to expel diplomats had nothing whatsoever to do with those sanctions," Pence said.

Upon further questioning from John Dickerson, Pence added, "I don't believe there were more conversations" as well as "I can confirm those elements were not a part of that discussion."

After the Pence interview, the Post reports, the Justice and intelligence officials thought the issue was "more urgent ... because U.S. intelligence agencies had reason to believe that Russia was aware that Flynn and Kislyak had discussed sanctions in their December call, contrary to public statements." Jan. 19, 2017 According to the Washington Post, Acting Attorney General Sally Yates, DNI James Clapper and CIA Director John Brennan discuss whom in the administration should be briefed on the Flynn-Kislyak communications. Jan. 26 and 27, 2017

The Justice Department notifies the White House counsel of discrepancies between what Flynn and Pence had claimed about the phone call between Flynn and Kislyak, as Spicer later reports at a Feb. 14 White House press briefing.

Jan. 30, 2017 President Trump fires Yates after she refused to defend his first travel ban. Feb. 8, 2017 In an interview, Flynn twice denies having discussed sanctions with Kislyak, according to the Washington Post. Feb. 9, 2017 A Flynn spokesman says that the retired lieutenant general "indicated that while he had no recollection of discussing sanctions, he couldn't be certain that the topic never came up," according to the Post.

This is also the day Pence "became aware of the incomplete information he'd received ... based on media accounts," according to Pence press secretary Marc Lotter, who spoke to reporters on Feb. 14.

Feb. 13, 2017 Kellyanne Conway tells MSNBC that Flynn "does enjoy the full confidence of the president."

Later in the day, Spicer says that Trump is "evaluating the situation" regarding Flynn.

That night, Flynn resigns as national security adviser. In a statement, he admits accidental wrongdoing:

"Unfortunately, because of the fast pace of events, I inadvertently briefed the Vice President Elect and others with incomplete information regarding my phone calls with the Russian Ambassador. I have sincerely apologized to the President and the Vice President, and they have accepted my apology."

The White House announces that retired Lt. Gen. Joseph Keith Kellogg Jr. will be acting national security adviser.

Feb. 14, 2017 Spicer says that 17 days prior, White House Counsel Donald McGahn had told the president that Flynn had been wrong when he told Pence he hadn't discussed sanctions with Kislyak, as reported by the New York Times. At a press briefing, Spicer says of the resignation, "We got to a point not based on a legal issue, but based on a trust issue," adding that Trump was "concerned that Gen. Flynn had misled the vice president and others." Politico reports that there's still more to come on the Flynn story, according to the ranking member of the House Intelligence Committee:

"Rep. Adam Schiff (D-Calif.) told House Democrats Tuesday that the recent revelations about former National Security Adviser Mike Flynn's conversations with the Russians are only the beginning, and more information will surface in the coming days, according to multiple sources in a closed party meeting."

Senate Majority Leader Mitch McConnell indicates that the Senate Intelligence Committee will investigate Flynn's contacts with Russian officials, and Sen. Roy Blunt, R-Mo., a member of the intelligence committee, says Flynn should meet with the committee "very soon."

With reporting from Barbara Van Woerkom Copyright 2019 NPR. To see more, visit https://www.npr.org.

(2017-02-14 05:00:00 UTC):

In a previous version of this story we incorrectly said transition officials confirmed the Dec. 29 conversation with Kislyak to NPR on Feb. 14. It was confirmed on Jan. 13.