Analysis: 'No recollection' has been an often-used Trump response
President Donald Trump has bragged that he has "one of the great memories of all time."
But - when faced with questions from special counsel Robert Mueller III about the 2016 campaign - Trump said his memory failed him.
When did Trump learn that his aides had met with a Russian lawyer offering dirt on rival Hillary Clinton?
"I have no recollection," Trump wrote in written responses to Mueller's team.
Did anyone tell Trump during the campaign that Russian President Vladimir Putin supported Trump's candidacy?
"I have no recollection of being told," Trump wrote back.
In at least 37 instances, Trump responded to Mueller's questions - about his campaign's contacts with Russians and about Russian interference in the 2016 election - by saying he couldn't recall.
It was an answer - or non-answer - that Trump had used repeatedly before.
He offered similarly hazy responses when he faced questions in a civil suit about Trump University, when he was pressed about his net worth in a deposition in another case, when reporters asked about his support for the Iraq War, and when he was quizzed about a key Oval Office encounter with then-FBI Director James Comey.
In the case of the special counsel investigation, prosecutors found Trump's repeated assertions of a faulty memory "inadequate," according to Mueller's newly released report.
Prosecutors pushed for an in-person interview.
"This is the President's opportunity to voluntarily provide us with information for us to evaluate in the context of all of the evidence we have gathered," they wrote, according to the report.
Trump declined - largely because his lawyers feared the president could misspeak or even lie, The Washington Post has previously reported.
In the end, the special counsel decided not to subpoena Trump for an interview, concerned it could lead to a drawn-out court battle, according to the report.
Trump's attorney Rudy Giuliani did not respond to a request for comment Friday about Trump's memory lapses.
Defense attorneys say there's nothing unusual about a witness - especially one who's the subject of an investigation - claiming not to recall key details. If they forgot, they forgot. And if they actually didn't forget, well, how do you show that someone's lying about the contents of their own mind?
"If they say they don't recall when they actually do recall, that actually is a false statement," and could carry legal penalties, said Jacob S. Frenkel, a former federal prosecutor who now works in the District of Columbia office of the law firm Dickinson Wright. "The problem is, how do you prove that?"
In the past, Trump has claimed memory lapses in several cases in which he was been asked to account for his own past statements. Instead of explaining them, Trump said he didn't remember making them in the first place.
"You don't remember saying that you have one of the best memories in the world?" an attorney once asked Trump during a 2015 deposition for a lawsuit against Trump University. The plaintiffs alleged that the university - really a series of real estate seminars - misled its customers into paying thousands of dollars for little benefit.
"I don't remember that," Trump responded. He had made the claim just three weeks earlier, in an interview with NBC News.
In that Trump University deposition - when lawyers were pressing Trump about his supervision of the school, starting 10 years earlier - Trump's forgetful response set the tone. He said "I don't remember" more than 30 times, and in 16 other instances responded to questions by saying it had been "too many years."
In that case, Trump later settled the lawsuit for $25 million.
In a 2007 deposition, Trump faced an attorney who wanted him to explain a claim he had made two years earlier to reporter Timothy O'Brien. The claim: Trump's net worth was $6 billion.
"You don't recall telling him you were worth $6 billion?" said attorney Andrew Ceresney.
"I do not. I do not," Trump said.
The claim was important in that case because Trump sued O'Brien for defamation, alleging that O'Brien had lowballed Trump's net worth in a book.
O'Brien's defense was intent on proving that Trump was an unreliable source of facts about himself - including this fact, about Trump's net worth. At the time Trump was claiming to be worth $6 billion, his accountants said he was worth less.
To disprove the claim, O'Brien's attorneys first needed to show Trump made it. After Trump said he didn't recall the statement, they produced a tape of the interview.
"What are you worth right now?" O'Brien asked on the tape.
"I would say six" billion, Trump said on the tape.
Trump's lawsuit against O'Brien was later dismissed.
In another lawsuit - this one over a failed plan for a Trump-branded building in Fort Lauderdale, Florida - Trump claimed to have little memory of his interactions with a business associate named Felix Sater. Sater had led the Fort Lauderdale project.
As recently as 2010, Sater had office space inside Trump's executive suites, and a Trump Organization business card. Sater said they had met one-on-one numerous times.
But in a 2013 deposition, Trump said he'd forgotten Sater so thoroughly that, "if he were sitting in the room right now, I really wouldn't know what he looked like."
Trump has repeatedly said he does not recall an episode Mueller closely scrutinized as a potential act of obstruction of justice by the president: a private Oval Office meeting he had in February 2017 with Comey.
The day before, Trump had fired national security adviser Michael Flynn after reports that he lied about his contacts with the Russian ambassador. According to Comey, the president asked to speak to him alone and then said he wanted to talk about Flynn, who was under investigation.
"I hope you can see your way clear to letting this go, to letting Flynn go," Comey recalled Trump saying. Comey said he did not commit to ending the investigation of Flynn, but took Trump's statement as "a direction."
Trump told the New York Times several months later that he didn't recall having a one-on-one conversation with Comey.
"Not even that I remember. He was sitting, and I don't remember even talking to him about any of this stuff," Trump said to the Times.
The president also denied Comey's account in public, tweeting in December 2017, "I never asked Comey to stop investigating Flynn. Just more Fake News covering another Comey lie!"
But the special counsel found that "substantial evidence" corroborated Comey's account, the report said.
Mueller cited as evidence a detailed memo Comey wrote of his encounter with Trump on the day it occurred and the fact that the former FBI director consistently described it under oath before Congress and in interviews with federal investigators.
Other administration officials confirmed to the special counsel that Trump shooed them out of the Oval Office to speak to Comey alone that day, the report said. And just hours before the encounter, Trump told New Jersey Gov. Chris Christie that firing Flynn would put an end to the Russia inquiries, the report said.
But in the end, Mueller was unable to ask Trump about his memory of the Comey meeting: The president's lawyers refused to allow him to answer questions from the special counsel about his actions in office.
This article was written by David A. Fahrenthold, a reporter for The Washington Post.