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Texas death row inmate Robert Roberson will not petition for clemency ahead of his scheduled execution in three weeks and will instead focus on obtaining a new trial in his capital murder conviction, his lawyer said Wednesday.

Roberson was convicted in 2003 for the death of his 2-year-old daughter, Nikki, who was diagnosed with shaken baby syndrome. Roberson has maintained his innocence over the two decades he has spent on death row, arguing that scientific evidence developed since his conviction invalidates Nikki’s diagnosis and shows that she died from chronic illness — not from being shaken so violently that she died, as prosecutors claimed at Roberson’s trial.

Roberson, 58, is scheduled to be executed on Oct. 16. His deadline to submit an application for clemency with the Texas Board of Pardons and Paroles is Thursday, 21 days before his execution date.

Under Texas law, a majority of the Texas Board of Pardons and Paroles must recommend clemency before the governor may grant it. Clemency in a capital case could mean a commutation of the sentence to life in prison and a reprieve of the execution, but would not affect the conviction.

Roberson’s application for clemency last year was denied by the board the day before he was set to be executed. His execution was then delayed by the Texas Supreme Court after a bipartisan group of state lawmakers undertook an extraordinary campaign to buy him more time — setting off a bitter political battle between members of the Texas House, who have pushed for a new trial, and Attorney General Ken Paxton, whose office now represents the state in opposing Roberson’s appeals.

In a statement, Gretchen Sween, Roberson’s lawyer, said that she advised Roberson not to apply for clemency again because it would offer a “grossly inadequate remedy.”

“A commutation of sentence is not justice for an innocent man who was wrongfully convicted of a crime that never occurred,” she said. “Relief for Mr. Roberson must come from the courts.”

Sween added that the board rejected Roberson’s application for clemency last year “without a hearing and without any explanation,” making it “impossible to discern what kind of information might be persuasive.”

“It is difficult to imagine a more robustly supported application than the one submitted for Mr. Roberson last year,” she said, adding that clemency would not “allow for the long overdue assessment of the objective medical evidence” in Roberson’s case and would ”only divert precious time and resources from the fundamental mission: obtaining a new trial for Robert at long last.”

Roberson filed a new appeal in August, citing new evidence brought to his legal team in June and claiming the judiciary in Anderson County — where he was convicted — acted unconstitutionally multiple times in his case.

His petition claims that Nikki was taken off life support at the direction of her grandparents — despite Roberson being her sole conservator — only after representatives of the Anderson County Judiciary falsely told hospital staff that the couple was Nikki’s legal conservators. Roberson was arrested for capital murder after Nikki died.

The filing also suggests that then-3rd District Court Judge Jerry Calhoon was improperly involved in the case and signed off on an order to provide Roberson’s legal counsel despite his son, Mark Calhoon, being a prosecutor in Roberson’s trial. The former judge did not preside over the trial.

Roberson also has an outstanding appeal at the Court of Criminal Appeals, Texas’ highest criminal court, presenting additional expert opinions finding that Nikki’s shaken baby diagnosis was unsound and that the autopsy ruling her death a homicide was flawed. That appeal also highlights the court’s decision in October 2024 to overturn the shaken baby conviction of a Dallas man.

Additionally, Sween noted that Gov. Greg Abbott has the authority to issue a one-time 30-day stay of execution.

In response to Roberson’s previous appeals, the state has maintained that the evidence backing his conviction still stands. Prosecutors have also sought to downplay the centrality of Nikki’s shaken baby diagnosis in his trial.

If Texas goes through with Roberson’s execution, he will become the first person in the United States put to death based on a shaken baby syndrome diagnosis.

“Mr. Roberson is actually innocent,” Sween said. “If he is executed, despite the overwhelming evidence of his innocence, Texas will commit an extreme miscarriage of justice.”

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