Wednesday's ruling comes after the Harris County District Attorney's Office wanted Cornelio to be removed from Ronald Lee Haskell's case after she ordered him back to Harris County under unusual circumstances last summer.
The initial motion for her recusal was filed Oct. 7, 2024, "based on conduct indicating that she has cast aside her role as a neutral, detached decision maker to become an advocate for death row inmate Ronald Lee Haskell," it reads.
Haskell was given the death penalty in 2019. He was charged with six counts of capital murder for the shooting deaths of six of his family members at their Spring home in 2014.
The crime was described as a "massacre" and the victims included four children, ages four to 13, and their parents, Katie and Stephen Stay. Katie was the sister of Haskell's ex-wife, whom he stalked, authorities said. Cassidy Stay, just 15 years old at the time, was the only survivor.
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Court records show that on June 27, Cornelio issued a bench warrant for Haskell to appear in her courtroom a month later at midnight.
The DA's office said that never happened, and they had no idea Haskell had been moved from TDCJ custody.
Instead, during Haskell's nearly three-week stay at the Harris County Jail, he called his mother, acknowledging the secretive nature of his presence, calling it "cloak and dagger," according to a jail call transcript.
He was also taken to a private imaging clinic near the Texas Medical Center for a scan as seen in still images from body camera video that were filed with the court.
Drue Lyon is Katie Stay's brother.
"The inmate was feet -- three or four feet -- away from some random guy sitting at the doctor's office, waiting for his name to be called. Did that guy know he was feet away from a mass murderer?" Lyon asked. "Who on Earth has that much power and authority? Who authorized that?"
The defense argued the state didn't have enough evidence to firmly prove Cornelio was incapable of impartiality, but on Wednesday, Judge Susan Brown ruled otherwise.
ABC13 spoke to Joshua Reiss with the Harris County District Attorney's Office following her ruling in their favor.
"What was very clear is that the victims of Ron Haskell were never going to have a fair shot," Reiss said.
Reiss named all Haskell's victims in his closing arguments.
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