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Good morning.

Here’s what you need to know:

What does Robert Mueller know?

• That’s what President Trump’s lawyers were left wondering after The Times reported this weekend that Donald McGahn, the White House counsel, had cooperated extensively with the Russia investigation by Mr. Mueller, the special counsel.

The president’s lawyers said on Sunday that they were confident that Mr. McGahn had said nothing harmful about the president during 30 hours of interviews that began in November. But they realized they hadn’t been given a full accounting of what Mr. McGahn had told investigators.

Mr. McGahn has repeatedly made clear to the president that his role as White House counsel is to protect the presidency, not Mr. Trump personally. People close to Mr. McGahn have said he fears that Mr. Trump will set him up to take the blame for any possible wrongdoing.