This piece was originally published on Just Security, an online forum for analysis of U.S. national security law and policy.

It has been reported that special counsel Robert Mueller is investigating President Donald Trump for possible obstruction of justice. With everything else that’s happened during this administration, the obstruction story can at times feel hard to keep up with. To try to help clarify that picture, here is a timeline of events that could be specifically relevant to Mueller’s obstruction of justice probe. If there’s an impeachment case to be made against the president, it likely will stem from Mueller connecting these dots.

Late July 2016: The FBI begins investigating the Russian government’s attempts to interfere with the 2016 election.

Jan. 6, 2017: FBI Director James Comey first meets President-elect Trump at Trump Tower as part of an intelligence community assessment briefing on Russian election interference. After the meeting ends, Comey privately assures Trump he is not being personally investigated. He writes a memo about the meeting after he returns to his car. Later testifying to Congress, Comey says, “I was honestly concerned that he might lie about the nature of our meeting, and so I thought it really important to document.”

Jan. 19, 2017: The New York Times first reports that U.S. law enforcement and intelligence agencies are conducting a counterintelligence investigation into links between Russian officials and Trump associates. The associates under investigation include former campaign manager Paul Manafort and advisers Carter Page and Roger Stone.

Jan. 27, 2017: According to Comey’s testimony, Trump invites Comey to what he believes will be a group dinner at the White House, but which turns out to be a private dinner meeting. Trump asks whether Comey wants to remain FBI director, and Comey responds affirmatively. During the dinner, Trump repeatedly tells Comey that he “needs loyalty,” and Comey responds, “You will always get honesty from me.” Trump responds, “That’s what I want, honest loyalty.” Comey responds, “You will get that from me,” hoping to end the conversation. Comey later testifies to that he believed the dinner was in part an effort to create a “patronage relationship.”

Feb. 13, 2017: National Security Adviser Michael Flynn resigns after revelations that he misled Vice President Mike Pence and other administration officials—and reportedly the FBI—about a conversation with Russian Ambassador Sergey Kislyak in December about U.S. sanctions against Russia.

Feb. 14, 2017: According to Comey’s Senate testimony: Comey and other IC leaders deliver a counterterrorism briefing at the Oval Office. Trump signals the end of the briefing by thanking everyone and saying he wanted to meet with Comey privately (Trump later denies this). Trump tells Comey, “I want to talk about Mike Flynn,” adding that Flynn had not done anything wrong but had to resign because he misled Pence. Trump then tells Comey, “I hope you can see your way clear to letting this go, to letting Flynn go. He is a good guy. I hope you can let this go.” (Trump later denies this.)

Immediately after the meeting, Comey prepared a memo of the communication and presented the issue to FBI senior leadership. Comey interpreted Trump’s communication as “a direction” to drop the FBI investigation into Flynn.

Shortly thereafter, Comey also met with Attorney General Jeff Sessions and told him that he felt the private meeting was inappropriate, without disclosing the details of the private meeting.

March 2, 2017: Sessions announces that he is recusing himself from any investigations into charges that Russia meddled in the 2016 election following revelations that he gave false testimony in his Senate confirmation hearings about his communications with Russians.

March 9, 2017: Trump’s assistant calls U.S. Attorney for the Southern District of New York Preet Bharara’s office and leaves a message asking Bharara to call Trump back. Bharara notifies an adviser to Sessions and calls Trump’s assistant to say that he cannot speak with the president directly because it is a violation of protocol.

March 10, 2017: Trump orders Bharara and 46 other U.S. attorneys appointed by Barack Obama to resign. The request surprises Bharara’s office because in November, he had met with Trump and advisers, including Steve Bannon and Jared Kushner at Trump Tower, and he says Trump had personally asked him to stay in the position. After refusing to resign, the next day Bharara says he’s been fired. His jurisdiction included Trump Tower in New York.

March 20, 2017: In testimony before the House Intelligence Committee, Comey confirms that the FBI is investigating whether members of the Trump campaign colluded with Russian efforts to influence the 2016 election. He also dismisses Trump’s claims that President Obama wiretapped him during the presidential campaign.

March 22, 2017: The Washington Post reports Director of National Intelligence Daniel Coats and other senior officials participate in an Oval Office briefing, after which Trump asks Coats and CIA Director Mike Pompeo to stay for a private meeting. Trump complains to them about Comey’s handling of the Russia investigation and asks them to intervene with Comey to get the FBI to stop investigating Flynn. During later Senate testimony, Coates and Pompeo refuse to answer questions about this meeting without offering an explanation of any legal basis for doing so.

Within a day or two of this meeting, Trump reportedly makes separate telephone calls to both Coats and NSA Director Adm. Michael Rogers, and requests that they issue public statements denying the existence of any evidence of collusion between Trump officials and the Russian government.

Then Deputy Director of the NSA Richard Ledgett reportedly writes an internal NSA memo documenting Trump’s conversation with Rogers. During the call, Trump reportedly questions the accuracy of the IC Assessment that Russia had interfered with the election.

In addition to Trump’s requests, the Post reports that senior White House officials separately requested that top intelligence officials consider the possibility of intervening with Comey directly to have the FBI withdraw its probe of Flynn. Their reported lines of questioning included: “Can we ask him to shut down the investigation? Are you able to assist in this matter?”

March 30, 2017: According to Comey’s Senate testimony, Trump calls Comey at his office and tells Comey that the Russia investigation is a “cloud” inhibiting his ability to act as president. Trump assures Comey that he has had nothing to do with Russia and asks Comey what he can do to “lift the cloud.” Comey responds that the FBI is investigating the matter as quickly as it can, and that a full investigation is in Trump’s best interests.

Trump repeatedly urges Comey to get the fact that he himself is not under investigation out to the public. Comey later testifies to the Senate that the FBI and DOJ were reluctant to make a public statement that they did not have an open case on Trump “for a number of reasons, most importantly because it would create a duty to correct, should that change.”

On the same day, the Wall Street Journal reports that Mike Flynn has informed the FBI and congressional officials of his willingness to be interviewed by House and Senate investigators as part of the investigation into Trump campaign ties to Russia, in exchange for immunity from prosecution. Flynn’s lawyer released a statement confirming only that discussions with congressional investigators were taking place, though it concluded: “no reasonable person, who has the benefit of advice from counsel, would submit to questioning in such a highly politicized, witch-hunt environment without assurances against unfair prosecution.”

March 31, 2017: Trump applauds Flynn’s request for immunity, tweeting:

April 11, 2017: According to Comey’s testimony: Trump calls Comey again and asks what he has done about Trump’s request to publicize the fact that he is not personally under investigation. Comey tells Trump that he relayed Trump’s request to Acting Deputy AG Dana Boente but that he has not heard back. Trump reiterates that the “cloud” is interfering with his ability to act as president, and asks whether he should have his staff contact Boente. Comey advises Trump of the traditional channel, which is for White House Counsel to contact DOJ leadership to make such requests. Trump says he will do so and tells Comey, “Because I have been very loyal to you, very loyal; we had that thing you know.” Comey responds by reiterating that the proper channel for Trump’s request is for Trump to follow the DOJ chain of command. Trump agrees and ends the call.

Comey later testifies that in light of Trump’s requests:

Our—our absolute primary concern was, we can’t infect the investigative team. We don’t want the agents and analysts working on this to know the president of the United States has—has asked—and when it comes from the president, I took it as a direction—to get rid of this investigation, because we’re not going to follow that—that request.

May 8, 2017: According to the New York Times: Trump summons Pence, his chief of staff, top lawyers, and other senior advisers to the Oval Office and informs them that he plans to get rid of Comey, showing them an at least four-page letter, single-spaced consisting of a long-running series of thoughts on why Comey should be fired that Trump dictated to aide Stephen Miller. The draft criticizes Comey for failing to publicly disclose that Trump was not personally under investigation and for his handling of both the Russia and Clinton email investigations.

White House Counsel Donald McGahn opposes the letter as “problematic” in multiple ways. His objections include the letter’s angry tone and its references to private conversations between Trump and Comey. He successfully convinces Trump not to use the draft. Deputy Attorney General Rod Rosenstein then composes his own letter, which becomes a central part of the administration’s public rationale for the removal. The New York Times reports that “Mr. Sessions had been charged with coming up with reasons to fire him,” according to administration officials.

This same day, Trump implicitly accuses former Acting Attorney General Sally Yates of leaking classified information in a tweet. Because Yates was scheduled to testify on the Flynn investigation before a Senate Judiciary subcommittee later in May, and because she had previously warned the White House that Flynn might have been compromised, this tweet could offer supporting evidence of an attempt to intimidate a witness in the Flynn investigation.

May 9, 2017: Trump fires Comey from his post as FBI director.

In the official announcement, Trump cites letters written by Sessions and Rosenstein that “recommend [Comey’s] dismissal.” The letters largely deal with the Clinton email investigation, and Trump also publicly cites Comey’s handling of the Clinton investigation in announcing the change. However, Trump’s letter also references the Russia investigation and Comey’s actions toward Trump personally: “While I greatly appreciate you informing me, on three separate occasions, that I am not under investigation, I nevertheless concur with the judgment of the Department of Justice that you are not able to effectively lead the Bureau.”

Of the two letters Trump cites, Sessions’ brief letter does recommend Comey’s dismissal, and cites the reasoning in Rosenstein’s letter. Rosenstein’s letter, however, does not explicitly recommend dismissal; instead, it only outlines Comey’s “serious mistakes” in handling the Clinton email investigation.

ABC News reports that Rosenstein was so upset at his letter being depicted this way that he was on the verge of resigning. Rosenstein tells the Sinclair Broadcast Group: “No, I’m not quitting.”

Late that night, the White House announces that Trump will meet Russian Foreign Minister Sergey V. Lavrov in the Oval Office the next day.

May 10, 2017: Trump meets with Lavrov and Ambassador Kislyak in the Oval Office and reportedly speaks to them about the Russia investigation and Comey’s firing. According to the New York Times, he tells the senior Russian officials: “I just fired the head of the FBI. He was crazy, a real nut job … I faced great pressure because of Russia. That’s taken off … I’m not under investigation.”

According to the Times, White House press secretary Sean Spicer did not dispute the account.

May 11, 2017: In an interview with NBC News’s Lester Holt, Trump admits that even before he consulted Rosenstein, “I was going to fire Comey. There’s no good time to do it, by the way.” Holt mentions that in Trump’s letter outlining the reasons for Comey’s firing, he cited Rosenstein’s letter, and Trump responds, “Oh, I was going to fire regardless of recommendation.”

He adds: “And in fact when I decided to just do it, I said to myself, I said ‘you know, this Russia thing with Trump and Russia is a made up story, it’s an excuse by the Democrats for having lost an election that they should have won.’ … This was an excuse for having lost an election.”

May 12, 2017: Trump tweets:

The suggestion is that Trump may have recorded such tapes and may decide to release them. The tweet follows a New York Times report the day prior describing the dinner between Trump and Comey and the alleged request for a pledge of loyalty.

Spokesman Sean Spicer denies that Trump was threatening Comey: “That’s not a threat. … He simply stated a fact. The tweet speaks for itself. I’m moving on.”

May 16, 2017: The New York Times reports on Comey’s allegations that Trump tried to pressure him to end the Flynn investigation and that he kept contemporaneous memos of his meetings with the president. The report includes the details that Trump cleared the room and that he allegedly told Comey: “I hope you can see your way clear to letting this go, to letting Flynn go. … He is a good guy. I hope you can let this go.”

May 17, 2017: Rod Rosenstein appoints former FBI Director Robert S. Mueller III to serve as the DOJ’s special counsel to investigate Russian interference in the election and possible coordination between Trump associates and Russia.

Trump decries the decision on Twitter:

According to later reporting in the New York Times: Shortly after Mueller’s appointment, Trump berates Sessions in an Oval Office meeting and tells him he should resign. Trump reportedly accuses Sessions of “disloyalty” and then launches into a series of insults against Sessions. Sessions becomes emotional and tells Trump he would quit, and then drafts and sends a resignation letter to the White House. Trump eventually rejects the resignation after senior administration officials argue that it would only create more problems for him.

May 18, 2017: Rosenstein testifies before a closed-door Senate briefing, reportedly saying that he knew Trump wanted to fire Comey before he wrote his letter justifying Comey’s removal. Rosenstein reportedly adds that Trump asked him to write the letter. He reportedly tells senators that on May 8 he knew that Trump was planning to fire Comey.

June 6, 2017: Washington Post reporter Robert Costa reports that Donald Trump was considering live-tweeting during James Comey’s upcoming Senate testimony.

June 7, 2017: DNI Coats and NSA Director Rogers both refuse to testify about their personal interactions with Trump and whether Trump asked them to intervene in the Russia investigation at a Senate Intelligence Committee hearing.

June 8, 2017: James Comey testifies under oath as to his interactions with Trump in the lead-up to his firing, publicly leveling his accusation that Trump tried to shut down the investigation into Michael Flynn and limit the Russia probe. Trump’s personal lawyer, Marc Kasowitz, responds to Comey’s testimony, claiming Comey “admitted that he unilaterally and surreptitiously made unauthorized disclosures to the press of privileged communications with the President.” Trump’s lawyers do not follow up on this dubious legal claim in any concrete way.

June 9, 2017: During a Friday press conference at the White House Rose Garden, Trump accuses Comey of lying under oath about the loyalty pledge and other things. He also says that he himself would be “100 percent” willing to give his version of the Comey meetings under oath and that he “would be glad” to speak with Robert Mueller about those meetings.

June 12, 2017: The Monday after the press conference at which Trump said he’d be “glad” to speak with Mueller, Trump friend Christopher Ruddy surfaces that Trump was considering firing Mueller.

June 13, 2017: The New York Times reports that a volatile and enraged Trump did want to fire Mueller but was subdued by his staff.

June 14, 2017: Multiple press outlets report that Mueller is looking into potential obstruction of justice by the president.

June 15, 2017: Trump implies via Twitter that the Mueller investigation is tainted:

June 16, 2017: Trump attacks Deputy AG Rosenstein—who is overseeing the investigation and would need to be the one to fire Mueller unless Trump replaced him—on Twitter:

June 22, 2017: Trump announces that he does not have taped recordings of his conversations with James Comey:

The New York Times notes that Trump’s tweet leaves open the possibility that others may have recorded their conversations.

July 8, 2017: The New York Times reports that Donald Trump Jr. arranged a meeting at Trump Tower with a Kremlin-linked Russian lawyer in June 2016, shortly after his father clinched the Republican nomination. Then–campaign manager Paul Manafort and Jared Kushner also attended. Though Trump Jr. initially releases a statement saying the meeting was primarily about an adoption program, emails released later show the meeting occurred because Trump Jr. was promised damaging information about Hillary Clinton by the Russian lawyer. Trump Jr. responded “I love it” to the prospect of colluding with the Russians.

Trump reportedly personally dictated the initial statement from Trump Jr., stating that he and the Russian lawyer “primarily discussed a program about the adoption of Russian children,” and that the subject of the meeting was “not a campaign issue at the time.” The claims in that statement were later proven to be false. Before the revelation of the president’s apparent involvement in these deliberations, Trump’s lawyer repeatedly denied Trump was involved in drafting them. Eventually, the White House confirmed that Trump “weighed in” on the drafting of the misleading statement.

July 10, 2017: Trump tweets that Comey illegally leaked classified information to the media, reiterating an unfounded claim his lawyer had previously made:

July 19, 2017: In an interview with the New York Times, Trump says that had he known Sessions was going to recuse himself from the Russia investigation, he would not have nominated him to be attorney general. Trump repeats that he relied on the Rosenstein letter in deciding to fire Comey. Trump asserts again that Comey leaked confidential information. He also mischaracterizes Comey’s description of the meeting where Trump allegedly pressured the then–FBI director to drop the Flynn investigation and denies that this mischaracterized version occurred. Trump also denies that he cleared the room to have this conversation with Comey.

July 21, 2017: The Washington Post reports that Trump had “asked his advisers about his power to pardon aides, family members and even himself in connection with the probe,” according to a source familiar with the effort. Such pardons might constitute obstruction of justice or an abuse of power.

July 24, 2017: The New York Times reports that Trump aide and son-in-law Jared Kushner met with Senate investigators looking into the Russia investigation on the Senate Intelligence Committee.

July 25–26, 2017: In a series of tweets, Trump renews his attacks against Sessions. He also repeated previous claims that Acting Director of the FBI Andrew McCabe had a conflict of interest with respect to the Clintons:

Aug. 1, 2017: In an interview with the Wall Street Journal, Trump again berates Sessions for recusing himself from the Russia investigation, saying he was “very disappointed in Sessions.” He also dismissed Sessions’ early support of his campaign as no “great” sign of loyalty.

Aug. 3, 2017: Vox reports that, in late May, McCabe told several people in high-level FBI management that they should consider themselves potential witnesses in any potential obstruction of justice investigation involving Trump. He reportedly told colleagues that he could also be a potential witness himself.

Aug. 31, 2017: The Wall Street Journal reports that Trump’s lawyers had met with Mueller several times and submitted several memos to him contending that Trump didn’t obstruct justice by firing Comey, and questioning Comey’s reliability as a potential witness.

Sept. 19, 2017: The Wall Street Journal reports that Mueller’s office interviewed Rosenstein in June or July 2017 about Trump’s removal of Comey. A source told CNN that Rosenstein has no current plans to recuse himself from the investigation, suggesting he does not view himself as a key witness in the obstruction of justice investigation. DOJ spokesperson Ian Prior released a statement saying, “As the deputy attorney general has said numerous times, if there comes a time when he needs to recuse, he will. However, nothing has changed.”

Oct. 12, 2017: Politico reports that a senior White House official is saying Trump’s legal team is considering trying to set up a meeting with Mueller.

Fall 2017: Foreign Policy reports that the White House turned over records to special counsel Mueller in the fall that indicated that White House counsel Don McGahn researched federal statutes regarding lying to investigators and violations of the Logan Act during the first days of the Trump presidency.

Oct. 19, 2017: CNN and Politico report that Trump has been personally interviewing candidates for high-profile U.S. attorney positions in the Southern and Eastern districts of New York. The candidates Trump has reportedly been interviewing have ties to the law firms representing close Trump allies. They include Geoffrey Berman—employed by the firm where Rudy Giuliani is a partner—for the Southern District position and Ed McNally—a partner at the law firm founded by Trump personal attorney Marc Kasowitz—for the Eastern District position. Both outlets report Trump had also personally interviewed current U.S. Attorney for the District of Columbia Jessie Liu before she was nominated by the president and confirmed by the Senate.

“For him to be interviewing candidates for that prosecutor who may in turn consider whether to bring indictments involving him and his administration seems to smack of political interference,” Sen. Richard Blumenthal (D-Conn.) tells Politico.

Preet Bharara, the former U.S. attorney in Manhattan, tells CNN’s Wolf Blitzer: “I understand that he’s personally interviewed the potential applicants for U.S. attorney in Manhattan and Brooklyn and one in Washington, D.C.—which happen to be places where Donald Trump has property and assets and companies—and not interviewed personally U.S. attorneys for other positions. … I think that reasonably raises a number of questions.”

Presidents rarely personally interview candidates for the 93 U.S. attorney jobs, and former President Barack Obama never interviewed a single such candidate during his presidency, according to MSNBC legal analyst and former Justice Department spokesman Matthew Miller.

Oct. 27, 2017: The Washington Post reports that U.S. Attorney for the Eastern District of Virginia Dana Boente has resigned.

Oct. 28, 2017: CNN reports that a federal grand jury has approved the first criminal charges in Mueller’s investigation.

Oct. 30, 2017: Mueller announces criminal charges against former Trump campaign chairman Paul Manafort and business associate Rick Gates. Both men plead not guilty to the charges, which center on money laundering and secret lobbying, and turn themselves into the FBI. Mueller also announces the unsealing of a plea agreement with former Trump foreign policy adviser George Papadopoulos, who it is revealed has been under arrest cooperating with the Mueller investigation since July 27. Papadopoulos pleaded guilty to lying to the FBI regarding his contacts with Russian officials while working for the Trump campaign.

Oct. 30–31, 2017: On Twitter, Trump dismisses the charges against Manafort and calls for the FBI to focus on Hillary Clinton and the Democrats. The next day, in another series of tweets, he minimizes George Papadopoulos’ role in his campaign, calling him a young, low-level volunteer.

Dec. 1, 2017: Michael Flynn pleads guilty to lying to the FBI about his contact with Russians during the presidential transition.

Dec. 2, 2017: President Trump tweets that he fired Flynn because Flynn lied to the FBI and to Mike Pence. This suggests that Trump knew that Flynn lied to the FBI when he allegedly asked Comey to drop the Flynn investigation the day after Flynn’s firing on Feb. 14. Trump’s request could thus be construed as an effort to impede an FBI investigation, and thereby to obstruct justice.

Within hours of Trump’s first tweet, news reports emerged that then-Acting Attorney General Sally Yates had informed White House counsel Don McGahn that Flynn had made false statements to the FBI and that McGahn had passed that information to the president.

The next day, Trump’s personal lawyer, John Dowd, confirmed as much to the Washington Post. Dowd also took responsibility for writing the tweet where Trump said he knew Flynn had lied to the FBI. According to the NBC News report, Dowd said he first drafted the tweet, then sent it to White House social media director Dan Scavino to publish. After NBC asked Dowd for a copy of the original email he sent to Scavino, Dowd told them that he dictated it orally.

Dowd said that Yates did not accuse Flynn of lying in her conversation with McGahn: “For some reason, the Department [of Justice] didn’t want to make an accusation of lying. … The agents thought Flynn was confused.” Dowd added: “All the president knew was that the department was not accusing him of lying.”

Dec. 3, 2017: Trump denies that he asked Comey to drop the Flynn investigation and attacks the integrity of the FBI investigation:

Dec. 4, 2017: Dowd claims the “President cannot obstruct justice because he is the chief law enforcement officer under [the Constitution’s Article II] and has every right to express his view of any case,” in an interview with Axios.

Dec. 12, 2017: President Trump tweets that the Trump-Russia investigation has wasted “thousands of hours” and spent “many millions of dollars:”

Dec. 21, 2017: FBI Deputy Director Andrew McCabe testifies in closed session before the House Intelligence Committee, reportedly confirming that former FBI Director Comey did talk with him about his conversations with President Trump soon after they happened.

The Washington Post reports that FBI General Counsel James Baker is being reassigned to other duties within the bureau by Director Christopher Wray. The president tweets:

Vox reported in June that Comey had told McCabe, Baker, and FBI chief of staff Jim Rybicki about Trump’s alleged efforts to shut down the Flynn investigation.

Dec. 23, 2017: The Washington Post reports that McCabe plans to retire early in 2018 when he becomes eligible for pension benefits. Former FBI Director James Comey laments Republican attacks on McCabe:

Meanwhile, the president tweets:

Dec. 24, 2017: President Trump renews his attacks on McCabe’s wife:

Dec. 26, 2017: Trump accuses the FBI of using a “pile of garbage” dossier as the basis for its Russia investigation, in response to a Washington Times report that was discussed on “Fox & Friends”:

Four days later the New York Times reports that it was actually the actions of George Papadopoulos that sparked the investigation.

This timeline was originally posted to Slate on Oct. 23, 2017. It has since been updated with additional items.

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