WASHINGTON — Special Counsel Robert Mueller has obtained a letter that President Donald Trump and a top political aide drafted in the days before Trump fired the FBI director, James Comey, which explains the president’s rationale for why he planned to dismiss the director.
The May letter had been met with opposition from Donald F. McGahn II, the White House counsel, who believed that some of its contents were problematic, according to interviews with a dozen administration officials and others briefed on the matter.
McGahn successfully blocked the president from sending Comey the letter, which Trump had composed with Stephen Miller, one of his top political advisers.
A different letter, written by the deputy attorney general, Rod Rosenstein, and focused on Comey’s handling of the investigation into Hillary Clinton’s private e-mail server, was ultimately sent to the FBI director on the day he was fired.
The contents of the original letter appear to provide the clearest rationale that Trump had for firing Comey.
The Times has not seen a copy of the letter, and it is unclear how much of Trump’s rationale focuses on the Russia investigation. Trump told aides at the time he was angry that Comey refused to publicly say that Trump himself was not under investigation, something Comey had told the president.
Comey later confirmed in testimony to Congress in June that he had told the president that he was not under investigation, but said he didn’t make that public because the status could change in the future.
Mueller is conducting a wide-ranging investigation into Russia and associates of Trump, including whether the president obstructed justice when he dismissed the FBI director.
The Justice Department turned over a copy of the letter to Mueller in recent weeks.
Miller drafted the letter at the urging of Trump during a weekend in May, when Trump and his team were at the president’s private golf club in Bedminster, New Jersey.
During that same weekend, as Trump and a small group of aides were in Bedminster devising a rationale for Comey’s dismissal, Attorney General Jeff Sessions and Rosenstein were working on a parallel effort to fire Comey.
Comey was fired May 9.
Trump lashed out anew at the former FBI director Friday, charging that Comey had “exonerated’’ Clinton before fully completing the investigation into her use of the private e-mail server.
In an early morning tweet that appeared to seize on a statement from two members of the Senate Judiciary Committee about Comey’s handling of the inquiry.
While the president had initially cited Comey’s conduct in the Clinton investigation as the reason for his ouster in May, he later conceded that he had been stewing about Comey’s focus on possible collusion between the Trump campaign and Russia to sway the election when he decided to dismiss him.
“Wow, looks like James Comey exonerated Hillary Clinton long before the investigation was over,’’ Trump wrote on Friday. “A rigged system!’’
Two Republican senators said Thursday that Comey had begun drafting his statement recommending not to charge Clinton before interviewing key aides in the investigation.
