House Democrats are almost certain to seek the evidence that Mr. Mueller received during the course of his investigation. A number of House committee chairmen are planning to ask executive branch agencies to preserve documents that they provided to the special counsel.

— Maggie Haberman

What would the worst-case scenario version of the report look like for Trump? What conclusions would it reach, and why would those be bad for Trump?

Dakota Gardner, Brooklyn

We don’t know what’s in the report. I don’t want to speculate on what the worst-case scenario might be. But we do know that the special counsel had been investigating whether the president obstructed justice when he fired James B. Comey, then the F.B.I. director, in May 2017.

Mr. Mueller had also been examining Mr. Trump’s ties to Russia and whether anybody associated with his campaign conspired with the Russians during the 2016 election. Mr. Mueller’s investigation led to charges against more than 30 people, but none of them tied the president to a Russian conspiracy.

— Adam Goldman

Why was Trump not interviewed? What effect will this have on the investigation?

Beth Long, Knoxville, Tenn.

We really don’t know the answer, but Mr. Trump’s lawyers consider it one of their greatest accomplishments that he never sat for an interview.

In early 2018, Mr. Mueller threatened to subpoena the president, setting off months of negotiations between the special counsel’s office and Mr. Trump’s lawyers. Ultimately, in November, Mr. Trump answered several questions in writing about what occurred during the campaign. But he refused to answer questions about his time in office — including whether he tried to obstruct justice. This meant that Mr. Mueller’s prosecutors were only left with the statements of other witnesses when they sought to determine why Mr. Trump may have interfered with the investigation.

Mr. Trump’s lawyers believed heading off an interview was such a great success because if he had testified, he would have been at risk of making an inaccurate statement and increasing his criminal exposure.

— Michael S. Schmidt