This week’s belated appointment of two new board members for the Office of Congressional Ethics suggests the independent watchdog agency is approaching the sixth anniversary of its creation with a fading shroud of controversy.

Judy Biggert, a Republican member of the House Ethics Committee during a particularly charged period, from 2001 through 2006, was Speaker John A. Boehner’s pick for the GOP opening. Biggert, who lost her bid in 2012 for an eighth term representing the Chicago suburbs, played a central role in the investigations and admonitions that led to the eventual downfall of her own majority leader, Tom DeLay, and in the investigation that found her leadership inattentive to House pages’ allegations of sexual advances by a GOP colleague, Florida’s Mark Foley.

Belinda Pinckney, an executive consultant and retired brigadier general, was chosen by Minority Leader Nancy Pelosi for the Democratic opening. Pinckney’s final military job, from 2007 to 2010, was as the Army’s top diversity officer. Earlier in her career, she was on the Pentagon’s team of liaisons to the Appropriations committees.

They are replacing a pair of former House members, Minnesota Republican Bill Frenzel and California Democrat Yvonne Brathwaite Burke, who had been on the board since the start but had been due for replacements for the past year. Five other original members remain, and look to do so for at least another year.

The office was created in 2008 to fulfill a Pelosi campaign promise — to “drain the swamp of corruption” at the Capitol — that was made on the way to winning House control in the previous midterm. The premise was to reduce the perception that the foxes were guarding the hen house in the House’s ethics process. So they turned some of the process over to an independent, bipartisan and knowledgeable panel, which would take on the initial job of reviewing and investigating allegations of misconduct by members and staff — and referring credible matters within three months to the Ethics Committee. That House panel still retains sole power to decide if the chamber’s rules or federal laws were broken and to propose sanctions by the full House. (There is no similar system in the Senate.)

Almost all the Republicans opposed creating the OCE, on the grounds that it was an unnecessary new layer of government. And plenty of Democrats came to dislike it, too, joining some GOP members in expressing regret that they’d given up any measure of control over their own reputations and political fortunes.

But a series of efforts to eliminate the panel, or neutralize its effectiveness with deep budget cuts, have all come up short. And the Republican leadership’s leanings toward closing the office when they took back the House in 2011 were abandoned because of opposition from the tea party freshmen, who had run campaigns as outsiders in favor of the strongest possible Hill ethics.

In the past two years, the volume of member criticism about the OCE’s operations has been reduced, while dissatisfaction has increased from attorneys in the niche business of defending politicians. They say their clients are given too little information about the investigations they’re named in, while having inadequate opportunities to respond to allegations against them.

In all of the 112th Congress, the OCE says it opened 32 investigations and ended up forwarding 13 to the House panel. The pace appears to have picked up last year; in just the first nine months of the 113th Congress, the OCE started 15 inquiries and forwarded seven to the House. (The next quarterly update from the OCE is due later this month.)

The two best-known referrals the Ethics Committee is reviewing: That Rep. Michele Bachmann of Minnesota may have improperly spent campaign money in a variety of ways during her campaign for the 2012 GOP presidential nomination, and that Democratic Rep. Timothy H. Bishop of New York may have sought to trade help with a constituent’s fireworks permit for a campaign donation. All the lawmakers deny wrongdoing.