Advocates were fighting for a Texas man’s life on Wednesday just hours before his scheduled execution in the death of his 2-year-old daughter, who prosecutors had argued was killed under the disputed cause known as shaken baby syndrome. The Texas Board of Pardons and Parole voted Wednesday against supporting clemency for 57-year-old Robert Roberson, who has spent more than 20 years on death row after being found guilty in 2003 of the murder of his daughter Nikki Curtis. Roberson is scheduled to be executed Thursday evening and would be the first person executed in a case involving the cause-of-death ruling, which a number of experts ― including the neurosurgeon who first described the syndrome in a research paper ― say has been misused in the criminal justice system to put innocent people behind bars .

A clemency board document obtained by HuffPost revealed all six parole board members voted against recommending commuting Roberson’s death sentence to a lesser penalty or granting him a 180-day reprieve of his execution. The matter is now in Texas Gov. Greg Abbott’s hands.

Roberson’s lawyers and medical experts who are supporting him are not arguing whether children die of abusive shaking but rather that doctors misdiagnosed Nikki’s injuries. Prosecutors did not consider other causes for her death at trial, and new evidence indicates the girl died of symptoms related to pneumonia, Roberson’s supporters said. Following the parole board’s recommendation, Roberso.