A Moroccan national who long served as a high-ranking diplomat to the United Nations is immune from a civil suit by a former Republican National Committee official whose trade secrets and personal information were leaked to U.S. media in a 2017 hack of his computer system, a Manhattan-based federal appeals court ruled on Friday.

A three-judge panel of the U.S. Court of Appeals for the Second Circuit said plaintiff Elliott Broidy and his Los Angeles-based investment firm had not established that the longtime Moroccan diplomat, Jamal Benomar, met the commercial activity exception under the Vienna Convention, which generally protects diplomats from civil lawsuits and criminal prosecution.

Broidy, a prominent Republican fundraiser who is represented by Steptoe & Johnson LLP, sued over the cyberattack in 2018, claiming that Qatar had plotted to discredit him on the belief that he was responsible for Trump's public criticisms of the country in June 2017. According to Broidy, Benomar had been acting as a paid secret agent of Qatar and was being paid to participate in the alleged hacking scheme.

During briefing, the State Department confirmed that the U.S. Mission to the United Nations had registered Benomar with full diplomatic privileges and immunities as of Nov. 13, 2018. But Broidy argued that the case could proceed because it stemmed from commercial and professional activities that Benomar took outside of his official capacity as a diplomat.

U.S. District Judge Cathy Seibel dismissed the case for lack of subject-matter jurisdiction and blocked Broidy's requests for jurisdictional discovery and for production of certain documents that Broidy said went toward his discovery motion.

On appeal, Broidy said that defendants should ultimately be required to show that no exception to diplomatic immunity applies.

Chief Judge Robert A. Katzmann acknowledged in a 23-page opinion that a number of courts, including the Second Circuit, had endorsed a "burden-shifting framework" for determining jurisdiction on foreign sovereign immunity claims. However, Katzmann said, there was "no justification" for extending that approach to immunity under the Vienna Convention.

"Accordingly, where a defendant has demonstrated diplomatic status, we hold that plaintiffs bear the burden of proving by a preponderance of the evidence that an exception to diplomatic immunity applies and that jurisdiction therefore exists," Katzmann wrote in the opinion.

He was joined by U.S. Circuit Judges Denny Chin and Christopher F. Droney.

A spokesman for Broidy said he has multiple lawsuits pending over the hack, and maintains that Qatar disseminated his information in an attempt to "silence him and take away his First Amendment rights.

"Mr. Broidy will continue to seek justice—and hold those who committed these acts accountable—by vigorously pursuing these cases," the spokesman said in a statement.

In upholding the lower court's dismissal, Katzmann said that it was "clear from the record" that deposition transcripts and phone records Broidy presented to the lower court did not establish by a preponderance of evidence that Benomar had even participated in the supposed smear campaign.

"Plaintiffs submitted no evidence whatsoever that Benomar was engaged in the activity or received the payments alleged, only a snippet of a deposition transcript that, viewed in the context of the additional transcript pages submitted by Benomar, is both unpersuasive and misleadingly out of context," Katzmann said.

"As plaintiffs failed to establish that the commercial activity exception to diplomatic immunity applied, we find that Benomar is entitled to diplomatic immunity under the terms of the Vienna Convention, and plaintiffs' claims against him were properly dismissed for lack of subject matter jurisdiction."

The ruling also rejected arguments that the district court abused its discretion in denying jurisdictional discovery and leave to amend the complaint.

Shannen Coffin, the Steptoe partner who represents Broidy, was not immediately available Friday to comment on the ruling.

Benomar is represented by Abbe Lowell, a partner with Winston & Strawn in Washington, D.C. Lowell did not return a call seeking comment on the decision.

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