The Texas Supreme Court on Friday ruled that a legislative subpoena cannot be used to stop an execution after Republican and Democratic lawmakers used the novel maneuver to pause Robert Roberson's lethal injection at the last minute. The ruling addressed a subpoena issued for Roberson by the Texas House Criminal Jurisprudence Committee last month that was seen as a way to delay his execution. But the high court ruled 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. 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. A new execution date for Roberson has not been set, but it is certain to move forward unless Gov. Greg Abbott grants a 30-day reprieve 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. Roberson, who was sentenced to death in 2003 for killing his 2-year-old daughter, Nikki Curtis. He 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. Roberson would be the first person in the United States to be executed for killing a child in this manner. 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. Moody insisted that Roberson could still be called to testify since the court ruling "reinforced our belief that the Committee can indeed obtain Mr. Roberson’s testimony and made clear it expects the executive branch of government to accommodate us in doing so.” Prosecutors said that Roberson killed his daughter by shaking her violently back and forth. Roberson's attorneys have argued that the child's symptoms did not align with child abuse and that she likely died from complications with severe pneumonia. His case has garnered support from nearly 90 lawmakers across party lines and civil rights advocates who say Roberson is innocent and that he has not been given a fair trial under the state's “junk science law.” The statute allows people convicted of a crime under outdated science to have their sentence overturned. The 2013 law was hailed as progressive and the first of its kind, however civil rights advocates say that the state's highest criminal court is not utilizing the law as they should for people facing execution. The Supreme Court, which handles civil matters, made clear it was not ruling on the merits of whether Roberson was guilty or innocent of capital murder or on the evidence in question. Those questions reside with the criminal courts, which have so far denied Robinson’s appeals, the Supreme Court said.