The House of Representatives on Wednesday adopted a resolution establishing an independent commission to investigate the conduct of the six-week U.S. military campaign against Iran, sending to the Senate a measure that would empower a 10-member bipartisan panel to subpoena administration officials, examine the legal memoranda underpinning the strikes, and produce a public report by next March.

The vote was 248-184, with 37 Republicans joining all 211 voting Democrats. The defection figure exceeded the projections of both whip operations as recently as Tuesday night and represented the largest Republican break from Speaker Mike Johnson’s leadership since the start of the 119th Congress. Six Republicans voted present, a maneuver several aides described as a face-saving alternative for members representing districts where opposition to the commission risked a primary challenge while a yes vote risked a general-election liability.

The measure, drafted by Rep. Theresa Holloway of Michigan and stripped of broader review authority in a Tuesday-night amendment, will direct the commission to focus on targeting decisions, intelligence handling, casualty reporting, basing posture in the Gulf and the post-ceasefire force drawdown. It excludes review of the underlying decision to use force, a concession Holloway said had been necessary to bring along the bloc of moderate Republicans whose signatures forced the floor vote two weeks ago.

“The American people are not asking us to relitigate March,” Holloway said in floor remarks shortly before final passage. “They are asking us to explain April. They are asking us why a Patriot battery was understaffed. They are asking us how a strike package costing $4 billion in a single morning was decided, and who decided it. Those are not partisan questions. They are answerable ones, and today this body has voted to answer them.”

Johnson, who voted no, told reporters in the speaker’s lobby after the gavel that the result was “the product of an honest debate that this conference was prepared to have” and rejected suggestions that the size of the defection signaled a loss of control over his caucus. “Thirty-seven members exercised their conscience on a narrow oversight question,” Johnson said. “That is not a fracture. That is a Republican Party that takes oversight seriously and a speaker who lets his members vote their districts.”

The 37 Republican yes votes included all four members whose signatures cleared the discharge petition on April 30 — Reps. Don Bacon of Nebraska, Brian Fitzpatrick of Pennsylvania, Mike Lawler of New York and Maria Salazar of Florida — joined by a larger group of suburban Republicans, plus three Texas Republicans and two Georgia Republicans whose districts include large veterans’ populations.

“I came to Washington to ask hard questions, not to schedule them away,” said Rep. Caleb Hartley of Pennsylvania’s 7th District, who had been listed as undecided as of Wednesday morning and announced his yes vote on the floor. Hartley’s district lost three service members during the war.

The political logic on the Republican side, aides said in interviews Wednesday afternoon, had hardened over the past 72 hours under the weight of the bipartisan Senate Armed Services report released Saturday that pegged the war’s direct cost at $218 billion; a Quinnipiac survey published Monday showing 69 percent of registered voters favoring an independent investigation, including 58 percent of Republicans; and a Tuesday memo from Cook Political Report shifting seven Republican-held districts from “Lean Republican” to “Toss Up.”

The administration’s response was muted. Press Secretary Karoline Leavitt, at a midday briefing that began roughly an hour before the final vote, said President Donald Trump remained “skeptical that any commission can add to what the intelligence committees already have” but stopped short of a veto threat. Two senior administration officials, speaking on condition of anonymity to discuss internal deliberations, said the president had been told Tuesday evening that a House majority was likely and had instructed aides to “shape the panel, not the headlines.”

Under the resolution, the commission’s 10 members will be named within 14 days of Senate passage and presidential action — five each from the majority and minority leaders of the two chambers, with the chair and vice chair selected jointly by the speaker and the Senate majority leader. The body will have subpoena authority and a one-year operating window, with a public report due no later than March 15, 2027, and the option of an additional three-month extension by majority vote of the commissioners.

The Senate is expected to take up the measure as soon as next week, with Majority Leader John Thune signaling in a brief floor statement Wednesday afternoon that he would move it on a calendar separate from the $89.4 billion war supplemental, which cleared the Senate 64-36 Tuesday evening and now awaits House action.

“The Senate is not going to slow this down,” Sen. Mark Warner of Virginia, who is leading negotiations with Sen. Susan Collins of Maine on a parallel resolution, told reporters outside the chamber. “We are going to take what the House sent us, make small technical changes, and pass it. The country has waited long enough.”

House Minority Leader Hakeem Jeffries, at a brief news conference after the vote, was measured. “Today the institution did its job,” Jeffries said. “Tomorrow it has to do it again on the supplemental, and again on the war powers resolution. We do not get to take a victory lap when 358 families are still waiting for answers.”

The war powers resolution, which cleared the Senate 58-42 on May 1, remains parked in the House Foreign Affairs Committee, where Johnson has said it will receive “appropriate consideration.” Two House Republican aides said Wednesday’s commission vote made a separate floor vote on war powers “all but inevitable” before the Memorial Day recess.

Holloway, asked after the vote whether the commission would be operating by midsummer, said only that she expected the Senate to act “before the end of next week” and that she had already received indications from both leaders that the joint nominating process could be completed “within the statutory window.”

Senate leadership aides said floor time for the commission resolution would be scheduled once the supplemental cleared the House, with a target final passage vote no later than May 15. Officials said the joint House-Senate nominating consultations would begin immediately afterward.