METRO’S BOARD of directors showed its ethical mettle when it undertook a no-holds-barred investigation into troubling questions surrounding the conduct of D.C. Council member Jim Graham (D-Ward 1) as a representative of the transit agency. But efforts to put the board’s house in order cannot stop with the findings of fact concerning Mr. Graham. The board must now determine if reforms are needed in the governance of the Washington Metropolitan Area Transit Authority.

An international law firm reviewed Mr. Graham’s 2008 actions and concluded that his attempt to barter a Metro development project for another matter before the D.C. Council violated Metro’s code of conduct. But it also issued a separate report on recommended changes to the agency’s policies and practices. Proposals by Cadwalader, Wickersham & Taft LLP included suggestions to strengthen Metro ethics rules (spelling out, for example, a prohibition against vote-trading) and to create an independent ethics committee to enforce the code.

The recommendations were discussed last month by the Metro board’s governance committee. As The Post’s Mark Berman and Luz Lazo reported, some members hesitated to make wholesale changes, while others favored dealing with the issue before another problem presents itself. There’s no question, as some board members argued, that Metro governance has undergone major changes since July 2011, when the board adopted its first bylaws and strengthened its code of ethics. Among the welcome reforms was the bid to end micromanagement by board members, with delegation of day-to-day operations and business matters to Metro’s general manager and staff.

Nonetheless, further improvements are in order. An outside law firm had to be retained to review Mr. Graham’s actions because board members are not subject to scrutiny by the agency’s inspector general. That needs to be fixed, though it’s not clear that a separate, and possibly costly, ethics committee is the most desirable solution. Cadwalader’s report also asked whether the Metro board meets too frequently, encouraging a culture of meddling in daily operations, and whether the board should continue to include elected officials, whose local responsibilities may conflict with Metro duties. Both questions are worthy of review. It’s encouraging that the board, which spared no effort in getting to the bottom of the allegations surrounding Mr. Graham, seems to agree and plans to take up these issues when it meets in February.