Transportation Secretary Anthony Foxx’s move earlier this month to place Washington’s troubled Metro under the direct oversight of the Federal Transit Administration wasn’t exactly what investigators had in mind when they called for federal intervention.

Foxx said the move would result in direct enforcement and investigation of the system’s safety issues by the federal government — including unannounced inspections and requirements that federal funds be spent on safety.

But the National Transportation Safety Board wanted federal transportation officials to place Metro directly under the oversight of a different agency, the Federal Railroad Administration. In a letter to Foxx on Sept. 30, NTSB Chairman Christopher A. Hart said the FRA was equipped to do the job.

The accident investigator had been looking into Metro’s safety practices following a series of mishaps, including a deadly smoke incident outside the L’Enfant Plaza Metro station in January. One passenger was killed and more than 80 were injured.

The NTSB told CQ Roll Call in a statement that it’s reviewing the Transportation secretary’s actions regarding Metro, formally known as the Washington Metropolitan Area Transit Authority.

That two federal agencies dealing with WMATA’s safety problems are at odds over how to proceed illustrates a broader transit safety issue: Safety investigators are skeptical that the FTA’s oversight capabilities will be strong enough to lead Metro to improve safety. That’s despite the fact that Congress granted the FTA greater power to enforce safety measures in 2012 under a surface transportation reauthorization law known as MAP-21.

“We are encouraged that Secretary Foxx also recognizes the urgency of correcting the safety issues at WMATA,” said NTSB spokesman Peter C. Knudson prior to Foxx’s Oct. 9 announcement of FTA’s takeover of Metro. “The NTSB will evaluate the proposed actions of the Secretary to see if they meet the intent of our recommendations.”

Congress gave the FTA greater power to enforce safety following an NTSB request to do so. In a report on the 2009 Metro collision that killed nine, the NTSB called for the department to seek additional legal authority from Congress to enforce transit safety. The NTSB said the FTA’s “lack of statutory authority to provide federal safety oversight” was a contributing factor to the accident.

Foxx pointed to the authority Congress granted the FTA when he announced it would oversee the Metro system, rejecting the NTSB’s recommendation that the railroad regulator take over.

He said the FTA had “greatly enhanced, independent safety oversight authority” as a result of the 2012 law that also allowed for a federal takeover if local agencies couldn’t do the job.

But the NTSB’s Sept. 30 letter suggested policy changes in 2012 would do little to address WMATA’s problems and referred to the FTA pace in establishing a regulatory framework that would allow the agency to fully employ its new authority.

Even if those rules were put in place, the agency would likely not be much more able to enforce safety than it was beforehand, the NTSB said.

“FTA enforcement authority will not change significantly under MAP-21,” the NTSB wrote in its letter. “Because the FTA’s safety authority primarily relies on [state oversight agencies], it does not wield the same regulatory enforcement tools to compel safety compliance that are available to other agencies such as the Federal Railroad Administration.”

But Foxx said an FRA switchover could create confusion because Washington’s subway and bus systems would be divided between two agencies: the FRA and the FTA. The move could also pose “a greater risk of slowing down improvements,” Foxx said, pointing to directives the FTA issued in June following an inspection of WMATA’s safety practices.

“We agree on the problem identified by the NTSB, but believe there is a faster, more effective way to address it,’’ Foxx wrote in the Oct. 9 letter.

Foxx’s announcement didn’t spark many comments from members of Congress whose constituents in Maryland, Virginia and Washington, D.C., are served by Metro. But Del. Eleanor Holmes Norton, D-D.C., issued a statement indicating she might still be willing to favor the NTSB’s approach.

“The FTA may be able to proceed on its own, but I will continue to work with my Republican colleagues and the Administration on appropriate language to be included in the upcoming surface transportation reauthorization bill,” Norton said on Oct. 9.

The NTSB asked the railroad administration to take over regulation of the troubled subway system after a series of mishaps and serious safety lapses on Metro’s trains this year. Following the January smoke incident, major safety concerns again rose to public prominence after a train derailed in August.

The August incident involved no injuries. The train was riding to position for commuter rush hour without passengers, WMATA said. But Washington’s transit agency later revealed the track problem leading to the derailment had been detected and left unrepaired for nearly a month before the accident.

While the NTSB and the Department of Transportation might not agree on what kind of federal takeover was needed, the two agencies agreed the local safety enforcer was ineffective.

Before the FTA stepped in, a committee comprised of representatives from Washington, D.C.; Maryland; and Virginia was tasked with overseeing safety. That group is known as the Tri-State Oversight Committee.

The NTSB said the committee “lacks the power to issue orders or levy fines and has no regulatory or enforcement authority.” The committee’s effectiveness was also called into question in a 2006 Government Accountability Office report.

Foxx indicated in his letter that the federal takeover was temporary and that the department would work with officials to come up with a better local oversight organization to oversee Metro.

With Foxx’s move, it’s less clear whether Congress will do anything about Metro oversight in a surface transportation reauthorization bill. But the safety issues have drawn the ire of the region’s lawmakers, who say it is time for a permanent general manager and other changes at the top.

Foxx also recommended a general manager be put in place at Metro immediately.

“WMATA needs new leadership. WMATA needs a turnaround artist to really take it over, an operating engineer to really bring about safety concerns,” Sen. Barbara A. Mikulski, D-Md., said in late September.

Democratic Sen. Benjamin L. Cardin, the junior senator from Maryland, also said the NTSB’s report signified a need for change, but hesitated to fully endorse the transition recommended by safety investigators.

“The current structure is not providing the accountability and direction we need,” Cardin told CQ Roll Call on Sept. 30. “There needs to be a federal responsibility here. I’m not opposed to that. This is the nation’s transit system. But I want to make sure that the local governments have an adequate input. So I’m not going to sign off totally on everything but it certainly needs a shakeup.”

Members of Congress have kept a close eye on Metro as safety and service questions have plagued the system. Lawmakers questioned officials about its viability at a hearing in July, with one lawmaker suggesting the transit agency should be privatized. The agency could also lose federal funding: A House appropriations bill outlined a $50 million cut to the Metro, though the Senate’s spending measure restored total funding for the agency in fiscal year 2016 to $150 million.