The Texas Supreme Court on Friday ruled that a legislative subpoena cannot stop an execution after Republican and Democratic lawmakers who say Robert Roberson is innocent used the novel maneuver to pause his execution at the last minute.

The ruling clears the way for Roberson’s execution to move forward, weeks after a bipartisan group of state House lawmakers bought him more time by subpoenaing Roberson as he waited to be taken to the nation’s busiest death chamber.

Roberson was sentenced to death in 2003 for killing his 2-year-old daughter, Nikki Curtis. He would be the first person in the United States to be executed over a conviction tied to “shaken baby syndrome,” a diagnosis that has been questioned by some medical experts.

A new execution date for Roberson has not been set, but it is certain to proceed unless Republican Gov. Greg Abbott grants a 30-day reprieve. Abbott did not move to do so before Roberson’s original execution date and his office challenged the subpoena tactic used by lawmakers, accusing them of overstepping their power.

The state’s all-Republican high court agreed, ruling that “under these circumstances the committee’s authority to compel testimony does not include the power to override the scheduled legal process leading to an execution,” wrote Republican Justice Evan Young, issuing the opinion of the court.

The ruling addressed a subpoena issued for Roberson by the Texas House Criminal Jurisprudence Committee. Roberson was scheduled to die by lethal injection on Oct. 17 when lawmakers, in a last-ditch effort, issued a subpoena to have him testify at the Texas Capitol days after his planned execution.

This spurred a legal conundrum between the state’s criminal and civil courts, which ultimately led to the Texas Supreme Court temporarily ruling in Roberson’s favor while it considered the matter. Roberson has gained bipartisan support from lawmakers and medical experts who say he was convicted on faulty evidence of “shaken baby syndrome,” which refers to a serious brain injury caused when a child’s head is hurt through shaking or some other violent impact, like being slammed against a wall or thrown on the floor.

Rep. Joe Moody, who has led the effort to stop Roberson’s execution, said delaying the execution with the subpoena was “never our specific intention” and added that the court “rightly agreed” that the subpoena and lawsuit were valid.