Correction: The name of board member Anthony R. Giancola has been corrected.

Metro board Chairman Mortimer Downey testifies on Capitol Hill, Friday, Feb. 13, 2015, before the House Oversight and Government Reform subcommittee hearing to examine safety gaps within Washington Metropolitan Area Transit Authority’s Metrorail system. (Molly Riley/AP)

The District’s inspector general has filed an ethics complaint against the chairman of Metro’s governing board, alleging that he violated conflict-of-interest rules in serving as a paid adviser to a company that has done tens of millions of dollars in contract work for the transit agency, according to a member of the board’s ethics committee.

Mortimer L. Downey, who joined the Metro board as a representative of the federal government in 2010 and became chairman this year, has made no secret of his lucrative ties to the engineering company Parsons Brinckerhoff, which has been paid $81 million in recent years to manage Metro’s capital improvements program.

The company, which also had a major role in designing and building the troubled Silver Spring Transit Center, has been sued by Metro and Montgomery County over alleged problems with the three-story transit hub. The center opened last week after five years of delays and $50 million in cost overruns.

Although Downey has said that his approximately $100,000-a-year job as a part-time “senior adviser” to Parsons Brinckerhoff was approved by Metro’s general counsel — and that he ended his 10-year relationship with the company three months ago — the Metro board’s ethics committee has received a conflict-of-interest complaint from the D.C. Office of the Inspector General, according to committee member Michael Goldman.

Goldman, a lawyer who represents Maryland on the board, would not disclose details of the confidential complaint, saying only that the inspector general has alleged that Downey’s involvement with Parsons Brinckerhoff was improper.

The inspector general’s office declined to comment. “As a matter of policy, we keep our complaints confidential,” spokeswoman Jaime Yarussi said.

Downey, a former deputy secretary of transportation in the Clinton administration, is chairman of Metro’s ethics committee. He said he has recused himself from the committee’s handling of the conflict-of-interest complaint.

Downey told The Washington Post earlier this month that under his deal with Parsons Brinckerhoff, which began before he joined the Metro board, he gave the company “strategic advice” on transportation projects. He said he initially worked eight days a month, then cut back to four days a month, and was paid about $100,000 annually.

He said Friday that he was aware of the ethics complaint but not its particulars. He said he wasn’t even sure that it involved his work for Parsons Brinckerhoff.

“Whatever it is, the [ethics] committee will look at what has been alleged and decide what to do,” Downey said. He said that he was careful never to get involved in Parsons Brinckerhoff’s Metro-related projects. And he said his relationship with the company was annually reviewed and approved by Metro’s general counsel.

Downey said that after the board came under growing public criticism for the transit agency’s financial woes and the subway’s chronic, sometimes calamitous breakdowns this year, he decided to end his involvement with Parsons Brinckerhoff to avoid generating more controversy for the agency.

It could not be determined whether the inspector general’s office issued the complaint before or after Downey severed his ties to the international engineering giant. But there are indications that the complaint was prepared several weeks ago.

“The committee may look at this [complaint] and say, ‘Forget it,’ ” Downey said. “Or they may decide to do something else. I really don’t know.”

Cliff Eby, a top Parsons Brinckerhoff official, told The Post this month that the company “diligently maintained” a “firewall” between Downey and Metro­related work.

The Metro board’s code of ethics lists possible sanctions for a member who violates the rules. Among other actions, the committee can issue a public reprimand, restrict the member’s involvement in Metro governance or request that the member be removed from the board by officials in Maryland, Virginia, the District or the federal government, depending on which jurisdiction the member represents.

As for the lawsuit against Parsons Brinckerhoff, Metro is seeking $25.8 million in damages, alleging poor design and management work by the company in building the Silver Spring facility, including deficiencies that Metro said will make the center more expensive to repair and maintain. Parsons Brinckerhoff has denied the allegations.

The four-person ethics committee is made up of Goldman; Catherine Hudgins, a board member from Virginia; D.C. Council member Jack Evans (D), who represents the District on the board; and Downey, the committee chairman. In this case, Downey will be replaced on the committee by board member Anthony R. Giancola , also a federal appointee.

Goldman, who will serve as the ethics committee chairman in Downey’s absence, said the complaint will be investigated by Metro’s chief ethics officer, Phillip Staub, who is also the agency’s chief counsel on human resources and civil rights issues. Staub will report his findings to the committee, Goldman said.

The complaint against Downey was prepared “a while ago,” Goldman said, and has been “kicking around the bureaucracy” for an unspecified period of time.

After drafting the conflict-of-interest complaint, Goldman said, the D.C. inspector general’s office initially sent it to the General Services Administration, the federal agency that appointed Downey to the Metro board. “The GSA eventually kicked it back and said they didn’t have the jurisdiction to investigate it,” Goldman said.

He said the D.C. inspector general next sent the complaint to Metro’s in-house inspector general, Helen Lew. “And she said, ‘Well, I can’t investigate board members,’ ” Goldman said. “So now it’s before the ethics committee.”

Unlike the board’s other committees — which deal with Metro’s safety, finances, governance and other issues — the ethics committee does not meet regularly. Its members convene only when issues such as the one involving Downey are formally brought to its attention. As a rule, the committee’s agendas and proceedings are confidential.

Last week, however, before the committee met behind closed doors Friday to discuss the Downey matter, its agenda popped up on Metro’s Web site. Then, a short time later, it vanished from the site, suggesting that it had been made public by mistake.

The agenda said only that the committee would be discussing a “complaint” from the D.C. inspector general’s office regarding Downey. After a reporter who saw the posting asked Goldman about it, Goldman confirmed that it involved Parsons Brinckerhoff and an alleged conflict of interest.