The Justice Department’s inspector general will investigate the FBI’s role in dropping plans a decade in the making to move its headquarters to the Washington suburbs, he told Congress in a letter Tuesday.

The inspector general, Michael E. Horowitz, told House committee leaders that he is initiating a review of actions at the DOJ and FBI that led to the canceling of the plans in favor of building a smaller replacement for the J. Edgar Hoover Building downtown and dispersing other FBI staff elsewhere.

The review could produce new revelations about the Trump administration’s stunning reversal of bipartisan plans for the development of a new, highly secure campus that would have gotten the bureau out of the fast-deteriorating Hoover building.

Democratic leaders of two committees, Elijah E. Cummings (Md.) and Gerald E. Connolly (Va.) of the Oversight Committee and Peter A. DeFazio (Ore.) and Dina Titus (Nev.) of the Transportation and Infrastructure Committee, have pressed Horowitz to investigate. They redoubled their efforts after the head of the General Services Administration was found by her agency’s inspector general to have made potentially misleading comments to Congress about the White House’s involvement in the decision-making.

Democrats allege that Trump used the decision to put his own financial interests ahead of the needs of the FBI and taxpayers, which administration officials deny. The GSA is the landlord to Trump’s D.C. hotel, located just down the street from the Hoover building, and redeveloping the Hoover site could introduce a new hotel competitor. Trump also told The Washington Post before running for office that he was considering bidding for the FBI project as well.

Under Trump, the FBI and GSA have both resisted responding to document requests made by Democrats on the Hill, though in a statement GSA officials said the agency “has produced more than 90,000 pages in response to respective Congressional Committee requests on FBI and the Old Post Office building since 2017.”

In a statement, the House committee leaders said: “For months, our Committees have investigated the Administration’s sudden change of heart on a federal property across the street from the President’s namesake hotel, but because the FBI has withheld key decision-making documents from Congress, we have been left with many unanswered questions.”

In April testimony to Congress, FBI Director Christopher A. Wray defended the decision to keep the headquarters in downtown Washington and reaffirmed it as his preference. “It is absolutely the FBI’s view, the FBI’s choice, the FBI’s preference to build a new building . . . at our current location,” he said.

For a decade before Trump’s election, the FBI had been working with the GSA and Congress on the suburban headquarters plan. Citing security concerns with staying downtown and the lack of large development sites nearby, the FBI and GSA pursued large plots of land near the Capital Beltway and suburban Metro stations, ultimately narrowing its search to sites in Greenbelt and Landover in Maryland and Springfield, Va.

But six months into the Trump administration, the FBI and GSA ditched those plans and then last year announced they preferred to keep a smaller downtown headquarters and move 2,300 headquarters staff members out of the Washington area altogether — to Alabama, Idaho and West Virginia.

GSA chief Emily Murphy testified that Wray — not Trump or a White House official — asked that the FBI remain downtown if possible, downplaying any White House role in the decision-making.

The FBI backed her assertion, but the inspector general found that Murphy’s testimony was incomplete and possibly misleading about the White House’s involvement, including an Oval Office meeting with Trump about the project that she omitted. Murphy denied misleading Congress, maintaining that the decision about where to put the FBI was made before that meeting.

The GSA maintains that the government could see cost savings under the new plan, but federal real estate experts have said the government’s expectations of cost savings weren’t likely to come true based on unrealistic expectations on the administration’s part about how little its plan will cost. The GSA inspector general found that the Trump administration plan could cost hundreds of millions of dollars more and accommodate 2,300 fewer employees.

Correction: This story has been updated to correctly characterize the GSA inspector general’s findings about Emily Murphy’s testimony. The IG found that her comments may have been misleading but did not conclude that she actively misled Congress.