The United Nations Appeals Tribunal has overturned a ruling in favor of a whistleblower who accused senior colleagues of retaliating after he alleged corruption in the U.N. peacekeeping mission in Kosovo, sparking protests.

James Wasserstrom, an American who was the lead anti-corruption officer at the Kosovo Mission in 2007, said the decision issued last weekend demonstrates that neither Secretary-General Ban Ki-moon nor the U.N. Ethics Office has “a credible interest beyond words in protecting the brave individuals who come forward after witnessing wrongdoing.”

The U.N. Dispute Tribunal ruled that Wasserstrom was subjected to “wholly unacceptable treatment” and “appalling” acts in violation of the rule of law and human rights and awarded him $65,000. Wasserstrom, who had sought $2.2 million in damages, appealed the award and the secretary-general appealed both the ruling and the award.

The Appeals Tribunal reversed the judgment and award in a 2-1 decision on grounds that the Dispute Tribunal can only rule on certain “administrative decisions.” In Wasserstrom’s case, it said “recommendations” by the Ethics Office, which was established to protect U.N. whistleblowers, were not “administrative decisions” that could be reviewed by the Appeals Tribunal.

The U.N.’s Staff Union in Geneva said the tribunal’s decision, which cannot be appealed, further exposes the shortcomings of the U.N.’s whistleblower protection system. It said a paper sent to the secretary-general’s management team by the U.N.’s staff unions in June revealed that since the Ethics Office was set up in 2006, it has protected less than one percent of the 343 staff who came to it for help.

“The Ethics Office has unfortunately become unethical,” Staff Union Executive Secretary Ian Richards said in a statement. “It encourages colleagues, serving in some of the world’s most dangerous locations, to blow the whistle on fraud and misconduct and then either does nothing to protect them or wriggles its way out of the problem.”

Shelley Walden of The Government Accountability Project, a Washington-based whistleblower protection organization that helped Wasserstrom, said the ruling “significantly weakened” the rights of U.N. employees and would likely lead to some other cases being thrown out by the tribunal.

“This is a sad day for whistleblowers and those who wish the U.N. was more accountable and effective,” Walden said.

U.N. spokesman Stephane Dujarric on Friday reaffirmed the secretary-general’s “strong support” for the work of the Ethics Office, which he said supports the Appeals Tribunal’s judgment.

A provision in the appropriations bill signed by President Barack Obama on Jan. 17, which was pushed by Wasserstrom, automatically withhold 15 percent of U.S. funding for the United Nations or any of its agencies unless or until Secretary of State John Kerry certifies to Congress that its conduct toward whistleblowers meets five “best practices.”

Wasserstrom said in a statement that the State Department and Congress should consider the tribunal’s decision “as all the evidence they need to act on the withholding requirement of U.S. law.”