UNITED NATIONS (AP) — The acting chief of the U.N. division that investigates wrongdoing in the world body is currently under investigation himself for allegedly retaliating against two whistle-blowers, according to a U.N. document.

Michael Dudley asked the U.N. Disputes Tribunal to suspend an investigation into the allegations — but tribunal Judge Marilyn J. Kaman, in a ruling released this week and obtained Wednesday by The Associated Press, rejected his request “in its entirety.”

Dudley questioned whether the whistle-blowers had acted in good faith and challenged the authority of the U.N. Ethics Office, which had determined that a “prime facie case of retaliation for each complaint existed.” He claimed his candidacy for the director’s position would be adversely affected by an “illegal investigation based on a malicious complaint” by an individual who had applied for the deputy director’s position that he now holds.

Usually, the investigation division of the Office of Internal Oversight Services, known as OIOS, investigates allegations of retaliation and other internal U.N. cases. But because Dudley is the division’s acting director and the whistle-blowers worked for OIOS, the Ethics Office asked Secretary-General Ban Ki-moon to approve an alternative investigation — which he did.

Kamen said the tribunal decided that Dudley was seeking “pre-emptive action” to block the investigation before the key decision on whether he engaged in retaliatory conduct. She said he did not meet the requirements for suspension, including showing that the investigation would be unlawful and cause him irreparable harm.

The Government Accountability Project, a Washington-based nonprofit organization dedicated to whistle-blower protection, had filed complaints of retaliation on behalf of the two staff members with the Ethics Office.

Bea Edwards, the organization’s international program director, told AP on Wednesday that the two individuals complained to the Ethics Office that they suffered retaliation at the hands of both Dudley and the former head of OIOS, Inga-Britt Ahlenius, who stepped down from the post last July. She said they have also submitted complaints to the Dispute Tribunal.

According to judge Kaman’s 15-page ruling, both staffers complained that Dudley retaliated after they had reported “concerns” about his behavior to Ahlenius. Edwards said their allegations involved “mishandling of evidence at OIOS.”

“The ruling shows the effectiveness of the U.N. Dispute Tribunal and it increases our confidence in the autonomy of the tribunal,” Edwards said.

She said “the alternative investigation is going on” right now.

The three members of the panel conducting the probe are former U.N. assistant secretary-general Yohannes Mengesha, retired Canadian judge Louise Otis, and South African businessman Len Konar, a former accountancy professor at the University of Durban, she said.

“It’s inexplicable (that Dudley’s) under investigation for tampering with evidence and he’s still acting director of the investigations division,” Edwards said.

The division’s management under Dudley, a career U.N. official, was criticized by some employees in a survey of staff in late 2008 obtained by AP.

An AP investigation last year also found that the United Nations cut back sharply on investigations into corruption and fraud within its ranks, shelving cases involving the possible theft or misuse of millions of dollars, and that Dudley had a record of closing cases before investigations were complete and not actively pursuing initiatives begun by a special anti-corruption unit, the Procurement Task Force, which was terminated in 2009.