The man accused of acting as the getaway driver in January's fatal shooting at a Des Moines school support program says he wasn't involved in planning the attack — and wants to call on his codefendant to testify to prove it.

Bravon Tukes, 19, and Preston Walls, 18, are charged with murder and other offenses in the Jan. 23 shooting at the Starts Right Here program, which killed two students and severely wounded program founder William Holmes, who also goes by Will Keeps. Prosecutors say Walls entered Starts Right Here and shot the victims, then left in a car driven by Tukes.

They were arrested a short time later after officers pulled them over.

In court filings, investigators have suggested victims 18-year-old Gionni Dameron and 16-year-old Rashad Carr were on the opposing side of Walls and Tukes in a long-running gang war, and that the shooting was the latest in a string of back-and-forth attacks stretching back at least 18 months.

Dameron and Carr's families have denied the claim.

Walls: Tukes 'got nothing to do with this'

Tukes and Walls are scheduled to stand trial together starting May 1, but in court Thursday, Tukes' attorneys asked Judge Lawrence McLellan to sever their cases to allow him to present testimony from Walls.

As described by Tukes' attorneys, prior caselaw has established a defendant cannot compel a co-defendant in the same trial to testify on their behalf, since doing so would violate the other defendant's right against self-incrimination. It is appropriate to sever trials to avoid this, the Iowa Supreme Court has held, if the defendant can show the co-defendant would be willing to testify, and that the testimony would be significantly helpful to their case.

Bravon Tukes appears in Polk County Court, Thursday, April 6, 2023. He and and Preston Walls are both charged with two counts of first-degree murder, one count of attempted murder, one count of willful injury, and one count of criminal gang participation in connection with the shooting at the Starts Right Here program on Jan. 23, 2023.(Photo: Zach Boyden-Holmes/The Register)

It's not clear whether Walls would agree to testify in a separate trial for Tukes — McLellan ordered the public and reporters to leave the courtroom so he and the attorneys could discuss that point Thursday — but in court filings, Tukes' attorneys say Walls has indicated Tukes was not involved in the attack.

According to recorded phone and video calls from the Polk County Jail, Walls "seem[ed] incredulous that Tukes has (the) same charges due to lack of involvement" and made statements that Tukes "got nothing to do with this."

"Defendant Walls appears to be steadfast in making statements that exculpate Defendant Tukes," Tukes' attorneys wrote.

Prosecutors have not filed a response yet to Tukes' motion to sever, and Assistant Polk County Attorney Stephanie Cox said Thursday they will do so by the beginning of next week. McLellan will then issue a written decision.

For subscribers: Starts Right Here's founder was shot helping at-risk kids. It won't stop him, friends say.

Walls' trial must start by end of May

Thursday's hearing also addressed a messy scheduling tangle. While the case is set for trial May 1, Tukes' attorneys have another trial set for that week. Although Tukes has waived his right to a speedy trial, Walls has not, meaning his trial must start no later than May 30.

Assuming the trials remain joined together, that leaves very few options. One of Tukes' attorneys has a second trial the week of May 8, when prosecutors have proposed holding the trial, and other attorneys have further conflicts later in the month. McLellan also is unavailable the weeks of May 12 and 30, further limiting the times available for the expected two-week trial.

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The judge noted it will be difficult to assign another judge to the case due to the number of other cases already scheduled for May.

"We just have a lot of things on the calendar in May that would pose that problem, so we may have to keep it on May 1," he said.

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If Tukes' trial is severed from Walls', his attorneys say they plan to postpone it to later in the year. While scheduling is not one of the factors to be considered in deciding whether to separate the trials, Tukes' attorney Jamie Deremiah said finalizing a trial date may have to wait until McLellan decides whether severance is appropriate.

"Practically speaking, (splitting the trials) would obviate the mess," he said.

Des Moines police, meanwhile, continue to investigate the shooting, and on Wednesday said they had issued a "material witness" warrant to speak to 18-year-old Kemoney Charles Lee McDuffy, who they believe has information about the attack.

William Morris covers courts for the Des Moines Register. He can be contacted at wrmorris2@registermedia.com, 715-573-8166 or on Twitter at @DMRMorris.

This article originally appeared on Des Moines Register: Separate trial requested by Starts Right Here murder defendant