Charlie Kirk’s widow and parents pleaded with a judge to allow the public to have more access to evidence in the case against the man charged with assassinating Mr. Kirk.

In a motion made public on Thursday, a lawyer for Mr. Kirk’s parents and widow, Erika, argued that all exhibits that prosecutors present during a preliminary hearing this week should be shown publicly in the courtroom.

Withholding evidence from public view “is not transparency,” wrote the lawyer, Jeffrey Neiman, and will only fuel conspiracy theories about Mr. Kirk’s death.

“At certain points throughout the preliminary hearing, the Kirk family sat in the room while evidence was admitted but not presented for their viewing,” Mr. Neiman wrote. “They were present in body yet denied the very thing their presence was meant to secure: their ability to meaningfully observe the preliminary hearing.”

Judge Tony Graf, who is overseeing the case, had on Wednesday ordered that portions of a video interview with the defendant’s former partner be redacted from public view. The video was shown in open court on Thursday with significant redactions.

Judge Graf has said he is balancing transparency with the right of the defendant, Tyler Robinson, to have a fair trial. He said on Thursday that he would continue to use a three-tiered system in which some evidence is allowed to be viewed only by the judge and the parties, some can be shown also to those in the courtroom gallery and some can be shown on the livestream.