After a recent court hearing in a high-profile, politically charged case, judges on the powerful federal appeals court in Washington received an onslaught of harassing, profane phone calls to their chambers. The angry calls from citizens unhappy with the views judges expressed during oral arguments prompted some on the U.S. Court of Appeals for the District of Columbia Circuit to remove their direct office phone numbers from the court’s website, two officials said.

The threats also hit home.

One judge’s personal phone number and street address circulated on Twitter with a message encouraging people to protest in front of the judge’s home. A picture of the house was also posted online.

The judge raced home to hunker down with family and soon after paid hundreds of dollars to personally install a new, more sophisticated video alarm system, according to one of the government officials who spoke on the condition of anonymity because of security concerns.

The heightened security steps reflect the rising number of threats against federal judges throughout the country. They also come as leaders of the federal judiciary ask Congress for help ramping up court protection after the attack this summer on the family of New Jersey District Judge Esther Salas. Her 20-year-old son was killed and her husband was critically wounded at their home by an embittered self-proclaimed “anti-feminist” who had filed a case before the judge.

“Criticism is part of the job; we’re used to it, and it doesn’t impact how we decide cases,” said Judge David McKeague, who leads the Judicial Conference’s Committee on Judicial Security and serves on the U.S. Court of Appeals for the 6th Circuit. But, he said, the concern is when the criticism “veers from being unhappy about a decision a judge makes to all of a sudden becoming, ‘You’re evil, biased or incompetent.’ ”

In the past three years, the number of threats tracked by the U.S. Marshals Service has dramatically increased as attacks targeting judges and their rulings have proliferated on social media.

“The concern is real,” McKeague said, “as evidenced by the rapid increase in threats and violent actions directed toward the judiciary.”

The animosity directed at judges is particularly persistent in Washington with legal battles over President Trump’s financial records and access to secret material from former special counsel Robert S. Mueller III’s Russia investigation.

District Judge Emmet G. Sullivan began receiving hundreds of calls, emails and letters in May after he refused to go along with the Justice Department’s unusual request to immediately drop the prosecution of Trump’s former national security adviser, Michael Flynn. The vast majority of the messages, according to another official who also spoke on the condition of anonymity to discuss the threats, were hostile. Many were laced with race-based profanity toward the judge, who is Black.

The Marshals Service, the official said, has since increased protection for the judge, who declined to comment for this story.

In August, a New York man was arrested after threatening to assault and murder a district court judge in Washington on or about May 14, when Sullivan put Flynn’s case on hold, according to a grand jury indictment unsealed this week in Washington.

The indictment of Frank J. Caporusso does not name Sullivan. But the dates align with Sullivan’s actions in court. The threat came in a voice-mail message left on the targeted judge’s office line, according to a detention memo filed in court.

“We are professionals. We are trained military people. We will be on rooftops. You will not be safe,” the message said. “Back out of this bullshit before it’s too late, or we’ll start cutting down your staff.”

Attorney William D. Wexler, who briefly represented Caporusso in New York, said “he denies the allegations.”

The Marshals Service is responsible for protecting about 2,700 federal judges nationwide, in addition to 30,300 prosecutors and court officials at more than 800 locations. Supreme Court justices have a separate police department in Washington.

In fiscal 2019, investigators reviewed more than 1 million derogatory social media posts. Deputies recorded about 4,500 “inappropriate” communications or threats directed a judges and other court officials, an increase of 40 percent from fiscal 2016.

It is a crime to threaten a federal judge, but not every nasty message or social media post is considered a threat, and deputies must balance free-speech considerations.

During the trial of Roger Stone, Trump’s friend, a photo of the presiding judge was posted on Stone’s Instagram account. The image of U.S. District Judge Amy Berman Jackson appeared next to what looked like a gun sight’s crosshairs. Stone deleted the post and apologized, saying he did not mean to threaten the judge.

In that case, Trump piled on, targeting Jackson in a tweet in which he also criticized the judge’s treatment of his former campaign chairman, Paul Manafort.

Troubling messages are more closely examined when there are multiple missives that use harsh language or an outright threat to physically harm the judge. Of the 4,500 potential threats tracked in fiscal 2019, 373 rose to a level that required deeper investigation, according to data from the Marshals Service.

Marshals Service Deputy Director Derrick Driscoll said personal information about judges, their families and other court officials is easier than ever to access online. Because of social media, “it’s easier to make threats or perceived threats,” he said. “The thing that’s not easier is the investigative side.”

Tracking down the people behind the phone calls, emails and tweets, and then showing up to knock on doors takes time.

The Administrative Office of the U.S. Courts is asking Congress for funds to hire 1,000 deputies; $7.2 million to install upgraded security systems in judges’ homes; and $267 million to replace and improve security cameras at 650 courthouses and related federal buildings.

Judiciary leaders are also recommending legislative fixes that would give judges permanent authority to redact certain information from financial disclosure forms and restrict online posting of personal information by government and private organizations. The list of proposed protected information includes personal data related to property tax records; car registration information; the employers of family members; and religious, organization, club or association memberships.

Gabe Roth, executive director of Fix the Court, which advocates for greater transparency, supports the physical security measures and hiring of additional deputies. But he’s concerned about access to public records and believes citizens should know more, for instance, about reimbursements for travel by judges.

“Unfortunately, being a public figure means some details of your life that you might wish weren’t public are made public,” Roth said in an email. “If the proposed legislation becomes law, and a federal judge is gifted a fancy house or car from a litigant, the public might never know about it. That’d be wrong and make it almost impossible to hold bad judges accountable.”

John F. Clark took over as director of the Marshals Service soon after the last deadly shooting of relatives of a federal judge in 2005. The killing of Judge Joan Lefkow’s husband and elderly mother at her Chicago home was the driving force behind the last package of security measures, including funds to install alarm systems in the homes of every judge.

“Judges are in a position that requires high security, but there is a balance because people have the right to know, hear and see” the court at work, said Clark, now head of the National Center for Missing and Exploited Children.

“It’s an extremely difficult assignment to provide a 24/7 package that some judges may want or expect. I’m hopeful that more resources can be provided for security, especially in a world that’s technology driven and increasingly open.”