A New Jersey man who has sued the United States for allowing “Socialists and Muslims” to hold jobs in federal government was charged with threatening a federal judge.

William Kaetz was arrested Sunday and charged with threatening to assault and kill a federal judge and using interstate communications to threaten to injure a person. He was scheduled to make an initial appearance by video-conference Monday afternoon.

Kaetz sent a letter to the judge's house last month saying he wanted the judge to expedite a case Kaetz had pending, according to the U.S. attorney's office in Newark. A week later he allegedly left a voicemail at the judge's office, and on Sunday allegedly sent an email to the judge’s personal email account calling the judge a traitor, which he said "has a death sentence.”

Kaetz also allegedly threatened to publicize the judge’s home address.

The 56-year-old Paramus resident’s arrest comes months after a disgruntled attorney shot and killed the son of U.S. District Judge Esther Salas’ home in New Jersey and wounded her husband in a targeted attack. Roy Den Hollander, who authorities identified as the shooter, later took his own life. The shooting spurred calls to restrict access to judges’ personal information.

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In Kaetz's case, the judge wasn't identified by the U.S. attorney's office in New Jersey, but court filings show that Kaetz has had at least three cases before U.S. District Judge Claire Cecchi in Newark.

A message seeking comment was left with Cecchi's office.

In one filed in March 2019, Kaetz, acting as his own lawyer, sued the federal government for $20 million, claiming his Constitutional rights had been violated because federal officials were guilty of “allowing known enemies of plaintiff's nation in plaintiff's nation's official offices.”

“It is well known fact that Socialists and Muslims will not assimilate to our constitutional republic form of government and all defendants have allowed demonstrations of advocacy to overthrow our constitutional form of government without prosecution,” Kaetz wrote, “therefore Socialists and Muslims and their supporters cannot be in any government job.”

Cecchi dismissed the case last October. Two weeks ago, Kaetz had filed a motion of reconsideration that demanded Cecchi be removed from the case.

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