A Florida man was sentenced to 14 months in prison after he admitted to calling the U.S. Supreme Court and Arvin Robertsthreatening to kill Chief Justice John Roberts, federal prosecutors announced Tuesday.

Neal Brij Sidhwaney of Fernandina Beach, Florida, called the Supreme Court in July and introduced himself by name in a voicemail before saying, "I will [expletive] you," court documents said. Sidhwaney, 43, was later arrested in August, according to court records.

He pleaded guilty in December to transmitting an interstate threat to kill, which carries a maximum penalty of five years in federal prison. A public defender listed as Sidhwaney’s lawyer in court records did not immediately return USA TODAY’s request for comment Tuesday.

Roberts was not identified by name in the indictment, which referred to him as "Victim 1." But a court-ordered psychological evaluation that was docketed in September before it was later sealed identified Roberts as the threat's recipient.

The evaluation, which POLITICO posted online before it was sealed, said a psychologist found Sidhwaney was competent to stand trial even though he suffered from "delusional disorder with psychosis."

The psychologist said Sidhwaney's functioning improved with medication, but he maintained a "paranoid belief system." His mother said he "becomes enraged watching the news," triggering him to write letters and emails or make phone calls.

A spokesperson for the Supreme Court did not immediately respond to USA TODAY's request for comment.

The development Tuesday comes as law enforcement officers face a surge in threats against court officials. The Marshals Service said serious threats against federal judges rose to 457 in fiscal year 2023, up from 224 in fiscal 2021.

Last month, President Joe Biden proposed $38 million in new funding to protect federal judges through the Department of Justice amid growing concerns about the safety of court officials.

Contributing: Reuters