A Vatican archbishop has been accused of bullying, overworking, and underpaying his staff during his tenure as papal envoy to the United Nations from 2010 to 2014.

A lengthy exposé published Monday by Crux, an online Catholic news outlet, said that Archbishop Francis A. Chullikatt, who received the 2014 Harry A. Fagan Award “for his defense of the poor and vulnerable,” has been accused of “serious moral and financial corruption” related to “the underpayment of staff, visa designations for certain employees, reporting of salaries to U.S. visa authorities, and related issues concerning U.S. labor laws.”

Former employees of the Holy See’s Mission to the United Nations describe their experience with Chullikatt as a “horror story,” while characterizing the man himself as “a power-hungry executive who launched an all-out war on those who dared to question his authority,” Crux reported

One former priest who worked for the mission said, “It was the closest thing I have seen in my lifetime to slavery.”

Senior level staff members of the mission reportedly confronted the archbishop in 2013, warning him that the mission should review both “the visa status and wage allocations for its employees” if he wished to avoid trouble from the U.S. government for labor law violations.

The archbishop allegedly ignored the warning and “became vindictive,” staff said.

Terrence McKeegan, who began as a legal advisor to the mission in August 2013, said he began noticing financial irregularities not long after he was brought on at the mission. McKeegan said that he and at least two other members of the staff had their salaries cut by Chullikatt by 40 to 60 percent from their contractual agreements, Crux said.

Both McKeegan and an unnamed senior staffer said employees were obliged to work long hours with “rare compensation” for their efforts, which entailed violations of standards as well as simple human decency.

A priest who worked at the mission said that “one man would drive the nuncio at times to Washington, D.C. for a brief meeting and then back again to New York City in the same day, only to have to don a different uniform on arrival and wait at tables all evening until midnight.”

“At times, their treatment by the nuncio, or the manner in which he spoke to them, left them shaking or in tears,” he said.

Pope Francis has repeatedly preached against unjust employers, saying it is a “mortal sin” to exploit one’s workers.

“Many Christians, even Catholics, who say they are practicing Catholics exploit people! They exploit their workers!” the pope said last Friday during his morning Mass.

“And so many of these call themselves Catholics. They go to Mass on Sundays and then they do this. This is a mortal sin!” he said.

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