WASHINGTON — The House Judiciary Committee authorized its chairman on Wednesday to use a subpoena to try to force the Justice Department to give Congress a full copy of Special Counsel Robert S. Mueller III’s report and all of the underlying evidence used to reach his conclusions.
The chairman, Representative Jerrold Nadler of New York, said he would not immediately issue the subpoena. But the party-line vote won by Democrats who control the committee ratchets up pressure on Attorney General William P. Barr as he decides how much of the nearly 400-page report to share with lawmakers.
“I will give him time to change his mind,” Mr. Nadler said in his opening statement. “But if we cannot reach an accommodation, then we will have no choice but to issue subpoenas for these materials.”
The committee also approved subpoenas for five former White House aides who Democrats said were relevant to an ongoing investigation into possible obstruction of justice, abuse of power and corruption within the Trump administration.
They included Donald F. McGahn II, a former White House counsel; Stephen K. Bannon, the president’s former chief strategist; Hope Hicks, a former White House communications director; Reince Priebus, the president’s first chief of staff; and Annie Donaldson, a deputy of Mr. McGahn.
Mr. Barr wrote in a letter to Mr. Nadler and other congressional leaders last week that he intended to give Congress a redacted version of the report by mid-April and would not share it with the White House before then.
Mr. Barr said that officials from the department and the special counsel’s office were scrubbing the document of four categories of information: classified material, secret grand jury testimony, details pertinent to ongoing law enforcement investigations and statements “that would unduly infringe on the personal privacy and reputational interests of peripheral third parties.”
That final category is so broad that House Democrats, who initially set an April 2 deadline for Mr. Barr’s delivery, have repeatedly said they will view as suspect anything short of an unredacted report and the evidence collected. During Wednesday’s hearing, Mr. Nadler argued that Republicans set the precedent for the subpoena during the last Congress, and they supported Democrats’ requests for documents and information during the investigations of Bill Clinton and Richard M. Nixon.
“The department is wrong to try to withhold that information from this committee,” Mr. Nadler said. “Congress is entitled to all of the evidence. This isn’t just my opinion. It is also a matter of law.”
But practically speaking, the subpoena does not ensure Congress will get what it wants. Mr. Barr could stall or outright defy their request, leaving the House with two options to enforce the subpoena: contempt of Congress proceedings or a court case. Both would take considerable time.
Republicans on the committee argued that Democrats were not on solid legal footing and were contorting past positions to serve their present political purposes. Representative Doug Collins of Georgia, the top Judiciary Committee Republican, said that though he shared Mr. Nadler’s interest in scouring Mr. Mueller’s investigation, the committee would be asking the attorney general to violate the law.
“As much as the chairman or I may want to view this material, it is a fundamental underpinning of our justice system and law that we cannot,” Mr. Collins said. “In the face of laws and rules he finds inconvenient, the chairman demands our nation’s top law enforcement official break the law instead of supporting him in enforcing it. This is reckless. It’s irresponsible. It’s disingenuous.”
Mr. Barr said the “principal conclusions” of the investigation found that the Trump presidential campaign did not take part in a conspiracy with Russia to undermine the 2016 election and that the evidence laid out by Mr. Mueller was insufficient to establish that the president had obstructed justice.