The Texas Supreme Court halted Thursday night’s scheduled execution of a man who would have become the first person in the U.S. put to death for a murder conviction tied to a diagnosis of shaken baby syndrome.

The late-night ruling to spare for now the life of Robert Roberson, who was convicted of killing his 2-year-old daughter in 2002, capped a flurry of last-ditch legal challenges and weeks of public pressure from both Republican and Democratic lawmakers who say he is innocent and was sent to death row based on flawed science.

In the hours leading up to the ruling, Roberson had been confined to a prison holding cell a few feet from America’s busiest death chamber at the Walls Unit in Hunstville, waiting for certainty over whether he would be taken to die by lethal injection.

“He was shocked, to say the least,” said Texas Department of Criminal Justice spokesperson Amanda Hernandez, who spoke with Roberson after the court stayed his execution. “He praised God and he thanked his supporters. And that’s pretty much what he had to say.”

She said Roberson would be returned to the Polunsky Unit, about 45 miles (72 kilometers) to the east, where the state’s male death row is located.

Roberson, 57, was convicted of killing of his daughter, Nikki Curtis, in the East Texas city of Palestine. His lawyers and some medical experts say his daughter died not from abuse but from complications related to pneumonia.

It is rare for the Texas Supreme Court — the state’s highest civil court — to get involved in a criminal matter.

But how the all-Republican court wound up stopping Roberson’s execution in the final hours underlined the extraordinary maneuvers used by a bipartisan coalition of state House lawmakers who have come to his defense.

Rejected by courts and Texas’ parole board in their efforts to spare Roberson’s life, legislators on Wednesday tried a different route: issuing a subpoena for Roberson to testify before a House committee next week, which would be days after he was scheduled to die. The unusual plan to buy time, some of them conceded, had never been tried before.

They argued that executing Roberson before he could offer subpoenaed testimony would violate the Legislature’s constitutional authority. Less than two hours before Roberson’s execution, a judge in Austin sided with lawmakers and paused the execution, but that was then reversed by an appeals panel. The Texas Supreme Court then weighed in with its order, ending a night of uncertainty.

Roberson is scheduled to testify before the committee Monday.

“This is an innocent man. And there’s too much shadow of a doubt in this case,” said Democratic state Rep. John Bucy. “I agree this is a unique decision today. We know this is not a done deal. He has a unique experience to tell and we need to hear that testimony in committee on Monday.”

Gov. Greg Abbott had authority to delay Roberson’s punishment for 30 days. Abbott has halted only one imminent execution in nearly a decade as governor and has not spoken publicly about the case.