BOISE, Idaho — Defense lawyers for convicted child killer Joseph Edward Duncan III have asked a judge to ensure that if a video showing Duncan torturing a child he later killed is shown to jurors, it is shown in open court.

The defense team made the request in a motion filed Friday, siding with media organizations that have argued for greater openness in Duncan’s death penalty proceedings.

Duncan, a convicted pedophile from Tacoma, pleaded guilty in December to 10 federal charges related to his 2005 kidnapping of two young siblings, Dylan and Shasta Groene, and the murder of Dylan. The children were snatched from their Coeur d’Alene home after Duncan fatally bludgeoned the children’s mother, Brenda Groene, their 13-year-old brother Slade, and the mother’s fiance, Mark McKenzie.

Three of the federal charges carry a potential death penalty, and it will be up to Duncan’s penalty phase jurors to decide whether he gets the death penalty or life in prison without parole. He earlier pleaded guilty to state charges in the deaths at the home; sentencing for those crimes is not at issue here.

On Thursday, U.S. District Judge Edward Lodge ruled that Duncan is mentally competent to face the death penalty hearing.

On Monday, Lodge plans a hearing to determine if Duncan should be allowed to represent himself. For now his three lawyers are still working on his behalf. Everyone involved in the case has been placed under a gag order by the judge.

In their motion on Friday, Duncan’s lawyers asked that some of the most shocking evidence be made public — a video depicting the “sadistic sexual torture” of young Dylan Groene in a remote cabin. Showing the video to a jury in a closed courtroom would violate First Amendment free speech rights as well as Duncan’s Sixth Amendment right to a public trial, the lawyers said. In the motion, the attorneys referred to Shasta and Dylan Groene by their initials.

“The entire sentencing trial will involve the description of Mr. Duncan’s kidnapping and abuse of S.G. and D.G. over the course of roughly six weeks, culminating in Mr. Duncan’s killing of the young boy. To be sure, the ‘cabin video’ is some of the most graphic evidence the government has elected to present in its desire to obtain a death sentence, but it is by no means the only such material,” the defense team wrote. “Closure for this part of the sentencing proceeding would not only be inappropriate, but ineffective.”

The bid to have the video aired in open court could be less about openness than an effort to get federal prosecutors to limit the amount of footage they’re willing to show the jury.

If prosecutors are so worried about keeping the video from public view, the defense lawyers wrote, they should “consider alternatives to playing of the video in its entirety for the jury.”

Still images from the video could be shown, the lawyers wrote, or a transcript could be handed out.

“The government has the power to make such a decision,” the defense team said. “What it cannot do is have it both ways: It cannot choose to present this evidence in pursuit of its goal of obtaining the death penalty and then trumpet the family’s privacy interests as the basis for denying the common-law and constitutional rights for Mr. Duncan and the public to have the evidence in this case presented openly.”

Earlier this year, several media organizations including The Spokesman-Review and The Associated Press filed a formal request that the judge unseal court documents and make the trial fully open to the public and the media. Lodge has yet to rule on that request.