The president of the United States has tried repeatedly to shut down an investigation into whether his campaign coordinated with Russian officials to help him win the 2016 election. Let’s review:

For a man who insists he has done nothing wrong, President Trump sure acts as if he has something big to hide. Mr. Trump‘s attempt to fire the special counsel, Robert Mueller, last June – which he backed off only when the White House counsel, Donald McGahn, threatened to resign over it – is only the latest in a long string of firings and lies that establish an undeniable pattern:

In January 2017, Mr. Trump asked James Comey, the F.B.I. director at the time, who was leading the Russia investigation, to pledge loyalty to him and to state publicly that Mr. Trump himself was not being investigated. Mr. Comey demurred on both counts.

In February, Mr. Trump fired his national security adviser, Michael Flynn, after public reports that he had lied to Vice President Mike Pence about his communications with Russian officials. (The White House had in fact been alerted to Mr. Flynn’s lies, and his vulnerability to blackmail, more than two weeks earlier.)

The next day, after an Oval Office meeting with Mr. Comey and other officials, Mr. Trump cleared the room and urged Mr. Comey to drop the investigation into Mr. Flynn.

In March, Jeff Sessions, the attorney general, recused himself from any investigations related to the 2016 campaign, after it was reported that he had failed to disclose his own contacts with Russians during the campaign. Mr. Trump tried to block the recusal, believing that Mr. Sessions should protect him from the Russia investigation. When Mr. Sessions recused himself anyway, Mr. Trump was furious.

Later that month, Mr. Trump asked top intelligence officials to intervene and persuade Mr. Comey to drop the Russian investigation. He also asked them to publicly deny that there was evidence of collusion between his campaign and the Russians.

In May, Mr. Trump fired Mr. Comey. The White House first claimed that Mr. Comey had been fired for mishandling the F.B.I.’s investigation into Hillary Clinton’s private email server. But two days later, Mr. Trump admitted on national television that he had fired Mr. Comey in order to stop the Russia investigation.

In June, we know now, Mr. Trump tried to fire Mr. Mueller, who had been appointed to take over the investigation only weeks earlier. Mr. Trump has denied that he ever made such an attempt.