1. President Trump may have tweeted himself into legal trouble.

The president’s tweets attacking Attorney General Jeff Sessions and the former F.B.I. director James B. Comey are being scrutinized as part of a broad inquiry into possible obstruction of justice.

The special counsel, Robert S. Mueller III, above, is examining whether the actions add up to attempts to obstruct the investigation by both intimidating witnesses and pressuring senior law enforcement officials to tamp down the inquiry.

Mr. Mueller wants to question the president about the tweets. Mr. Trump’s lawyers said that none of the evidence Mr. Mueller is looking at constitutes obstruction.