The investigation moves to the Capitol.

The investigation of Mr. Trump’s activities related to Russian interference in the 2016 presidential election, including efforts to impede the inquiry, is moving from the executive branch to Congress, where the matter is anything but resolved.

Representative Jerrold Nadler, Democrat of New York and chairman of the House Judiciary Committee, issued a subpoena on Friday, demanding that the Justice Department hand over the complete and unredacted version of the report and all of the underlying materials by May 1.

[Read the subpoena.]

“Even the redacted version of the report outlines serious instances of wrongdoing by President Trump and some of his closest associates,” Mr. Nadler said on Friday. “It now falls to Congress to determine the full scope of that alleged misconduct and to decide what steps we must take going forward.”

Mr. Nadler has said it is too early to decide whether impeachment proceedings are warranted.

He and other Democrats criticized the attorney general for a sparse summary of the report favorable to the president last month and for publicly defending the president and making excuses for some of his actions during a news conference on Thursday morning before the report was even released.