A Utah judge will decide Monday if accused assassin Tyler Robinson can appear in civilian clothes during future court appearances after a tense legal battle ended in a closed-door hearing Friday afternoon.

Lawyers for the 22-year-old alleged killer and state prosecutors met privately before District Judge Tony Graf after a secret Monday motion sought to block the defense's bid to let Robinson -- charged with gunning down conservative firebrand Charlie Kirk -- ditch his shackles and prison duds for a suit in court.

In the classified filing, reportedly co-authored by the Utah County Sheriff's Office, prosecutors claimed the legal doc contained "secure information that might endanger personal and public safety if disclosed," the Salt Lake Tribune reported.

On Tuesday, the defense pushed back, urging the judge to strike the state's response, insisting it should come exclusively from the Utah County Attorney's Office and not jointly filed with the sheriff's office.

The state, in another filing Wednesday, argued that law enforcement has the legal right to respond to motions and that joint filings are "both appropriate and efficient," noting that the sheriff's office was specially asked to respond because it oversees court security, ABC 4 reported.

The sheriff's office also asked the judge to limit media coverage of the high-profile case.

After Robinson's attorneys filed a reply Thursday, reinforcing their original motion, Graf let the opposing lawyers hash out the issue behind closed doors in the Provo courthouse ahead of a public hearing Monday afternoon, where he will issue his final ruling on the accused gunman's court attire.

The legal showdown began after Robinson's defense filed a motion on Oct. 9, arguing that photos showing him in a prison jumpsuit and restraints could bias potential jurors and jeopardize his chance at a fair trial.

Robinson -- who is accused of fatally shooting the Turning Point USA founder during a speaking event at Utah Valley University on Sept. 10 -- was sported a "suicide smock" during a virtual hearing last month.

Robinson was charged with aggravated murder and other offenses, and could face the death penalty under Utah law -- a punishment publicly supported by President Trump, a close friend of Kirk.

Utah is one of five states that still use a firing squad as a method of capital punishment.

Robinson has not yet entered a plea on his charges.

Judge to make ruling on Tyler Robinson's civilian clothes request...