Man Faces Execution After Daughter's Death Was Ruled Shaken Baby Syndrome. But Lead Detective Thinks He Got It All Wrong

A judge denied a motion to vacate the execution of Robert Roberson, who was convicted of murdering his 2-year-old daughter in 2002

<p>Texas Department of Criminal Justice</p> Robert Roberson

Texas Department of Criminal Justice

Robert Roberson

A Texas judge denied a motion to vacate the scheduled execution of death row inmate Robert Roberson, who was sentenced to death for the 2002 killing of his 2-year-old daughter, Nikki Curtis, despite his attorneys' claims that the girl's death was actually the result of chronic illness.

The Innocence Project, which has taken up Roberson's defense, said the motion was denied on Tuesday, Oct. 15.

“It is terrifying that Robert, an innocent, disabled man with the most gracious heart, is scheduled to be executed under an invalid warrant issued by a seemingly biased judge in just two days’ time," Roberson's attorney Gretchen Sween said in a statement. "Governor [Greg] Abbott can prevent an irreparable mistake by commuting Mr. Roberson’s death sentence or, at the very least, granting him a reprieve so that the overwhelming evidence that no crime occurred can be heard."

Roberson, 57, is scheduled to receive a lethal injection on Thursday, Oct. 17, in connection with Nikki's death, which prosecutors claim was a result of shaken baby syndrome, a diagnosis that refers to a serious brain injury caused when a child’s head is injured through shaking or some other violent impact, the Associated Press reported.

But critics of the diagnosis say doctors have not considered instances such as short falls with head impact and naturally occurring illnesses like pneumonia, which could mimic an inflicted head injury. The diagnosis presumes there was abuse and doesn’t allow for the possibility of other factors.

Roberson’s attorneys argue Nikki’s death was not the result of abuse, but of acute viral pneumonia and inappropriate medication prescribed by doctors.

"She was as sick as could be from pretty much the time she was born," says Jason Flom, co-founder of the Innocence Project and host of the podcast Wrongful Conviction. "She had 47 hospital and doctor visits in her two short years of life."

Last month, a group of Texas lawmakers went to Huntsville, Texas, to raise awareness about Roberson. They were a part of a group that included 86 bipartisan legislators who signed a letter urging the state to grant clemency to Roberson. The group expressed “grave concern” that Texas was going to execute Roberson “for a crime that did not occur,” according to the letter. The lawmakers cited “voluminous new scientific evidence,” according to The Texas Tribune.

In the state's objection to a stay of execution filed on Oct. 9 and reviewed by PEOPLE, prosecutors say that there was evidence that the child was both shaken and that she had suffered abuse at the hands of her father.

"Everything that [Roberson] continues to complain of has been litigated in state and federal court, and every court has rejected his arguments," prosecutors wrote.

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But Brian Wharton, the lead detective in the case that investigated Nikki’s death, says he believes Roberson is innocent, especially after learning that Roberson was diagnosed with autism in 2018.

Roberson’s attorneys argue that his “flat demeanor,” which they say stems from his diagnosis, contributed to his conviction because prosecutors cited it as a “sign of culpability,” The Texas Tribune reported.

“I will be forever haunted by my participation in his arrest and prosecution,” Wharton stated in a letter of support for Roberson’s clemency. “He is an innocent man.”

As the state of Texas continues to head toward execution, Flom is determined to do what he can to reach out to people with power to stop it.

"It's such a combination of a scramble and a moral imperative," Flom tells PEOPLE. "You’re left wondering, have we done everything? Is there anyone else who could be helpful that we haven't thought of yet?”

He says, "This is not just about Robert, but about preventing future tragedies."

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