Dennis Martire, middle right, member of the Metropolitan Washington Airports Authority. Martire was effectively forced off panel and will leave next month to make way for GOP appointee. (Dayna Smith/FOR THE WASHINGTON POST)

Labor official Dennis L. Martire, who has spent months fighting his ouster from the Metropolitan Washington Airports Authority board, will step down in October, he said Wednesday.

Martire’s announcement came after the board agreed to a confidential settlement that ends a dispute with Virginia Gov. Robert F. McDonnell (R), who has criticized Martire for expensive travel and who has been working to exert more influence over MWAA.

The embattled board also approved new ethics rules that will prohibit members from accepting expensive gifts from people who do business with the authority.

MWAA’s actions mark an effort to turn a corner after a run of bad publicity over questionable board member travel, contracts with former board members and other ethics issues. But in keeping many details under wraps, MWAA’s handling of both the settlement and the new ethics policy raised questions about the authority’s commitment to transparency.

The vote on Wednesday on the new ethics policy had been expected, but it was only this week that the possibility began to emerge of a settlement in the dispute involving Martire.

In June, McDonnell removed Martire, a Democrat, from the board and appointed McLean businesswoman Caren Merrick to replace him.

At the board meeting Wednesday, MWAA’s directors announced the settlement, which allows Martire to resume his duties as a board member. But minutes after Martire took his place at the board table, he announced that he would resign from the 13-member board.

“This case would have gone on for months,” Martire said of his legal challenge. “While I think the fight was worth fighting, it just doesn’t make sense to spend millions on litigation.”

Although no laws or policies appear to have been violated in the incidents detailed in news accounts and an inspector general’s report, the revelations have fueled criticism of MWAA, whose role overseeing construction of Metrorail’s $5.6 billion Silver Line has made the authority the subject of intense scrutiny.

MWAA, whose board is made up of representatives from the District, Maryland, Virginia and the federal government, operates Reagan National Airport, Dulles International Airport and the Dulles Toll Road.

Martire was one of five Virginia representatives on the board and revelations about his expensive business travel made him a target of MWAA critics, including McDonnell, who has been working to expand his influence with the powerful authority.

“We are happy to put this unnecessary and expensive distraction behind us and look forward to continuing to improve the accountability of the Metropolitan Washington Airports Authority,” McDonnell said in a written statement.

The controversy over Martire’s conduct even spilled into a U.S. Senate race between former Virginia governors Timothy M. Kaine and George Allen. Martire, an official with the Laborers’ International Union of North America, was appointed to the board by Kaine, a Democrat. Allen, a Republican, had repeatedly called on Kaine to tell Martire to relinquish the MWAA seat. According to the Loudoun Times-Mirror, Kaine asked Martire in June to step aside.

With the Martire matter settled and a package of travel and ethics reforms now in place, MWAA officials hope to put the problems of the last few months behind them and turn the focus to other matters, such as securing additional federal funding for the second phase of the Silver Line rail extension. Under a law passed by Congress, the MWAA board is to expand, and on Wednesday, D.C. Mayor Vincent C. Gray (D) announced that he was nominating Barbara Lang, chief executive of the D.C. Chamber of Commerce, to take the city’s new seat on the board.

Despite the board’s recent actions, questions remain about its commitment to transparency. Michael Curto, chairman of the MWAA board, heralded the approval the new ethics policy as a “a roadmap to public trust,” yet officials had refused to allow the public to review the proposed ethics rules. Moreover, details of the settlement with Martire are confidential, and Martire declined to comment on the terms.

Keeping such information from the public “is the wrong approach,” said Rep. Frank R. Wolf (R-Va.), whose district is home to Dulles and whose concerns prompted a federal review of the way the board does business.

“They’re not dealing with nuclear secrets over there,” Wolf said. “Absent some compelling reason that information has to be so private — because of competition over bringing in another airline or something like that — my position is be transparent. The public needs to know what they’re doing.”

For a time, it seemed that the dispute involving Martire might drag on for months or years. Martire contended his dismissal was politically motivated. But the fact that Martire spent $38,000 attending five conferences in 2010 and 2011, including more than $9,000 on a plane ticket to Prague, damaged the labor leader’s credibility and made him an easy target for MWAA critics.

Reports that board members spent lavishly on their own travel and entertainment, that former board members were awarded no-bid consulting contracts and that one was hired to a six-figure job the day after she gave up her board seat earned the group a sharp rebuke from the nation’s top transportation official, the governors of Maryland and Virginia, and the District’s mayor. In July, Transportation Secretary Ray LaHood appointed a federal lawyer to monitor MWAA’s operations.