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The Texas Supreme Court is weighing this death row inmate Robert Roberson The man, whose death sentence was temporarily stayed last month, must testify before a Texas House committee before the state carries out his execution.

The state’s highest civil court temporarily stayed Roberson’s execution last month after the House Criminal Jurisprudence Committee subpoenaed the man on Oct. 16 and called on the 57-year-old East Texan, who was convicted of killing his 2-year-old daughter, to testify about his crime. Trial at the Texas Capitol four days after the scheduled execution.

That subpoena triggered an unprecedented question about the state constitution’s separation of powers: do subpoenas of legislatures take precedence over the executive branch’s authority to impose the death penalty, or vice versa?

Here’s what you need to know.

(There are conflicting portrayals of Robert Roberson’s murder case. Here’s what you need to know.)

Background: Roberson was convicted in 2002 of killing her chronically ill 2-year-old daughter, Nikki Curtis, who she said fell out of bed at the family home in Palestine before taking her to the emergency room. A doctor diagnosed Nikki with: shaken baby syndromeThis assumes abuse.

Roberson’s defense attorney did not dispute the diagnosis during the hearing, arguing only that Roberson did not intend to kill his daughter. But in the years since the trial, new scientific and medical evidence Research has emerged showing that symptoms associated with shaken baby syndrome may also indicate naturally occurring medical conditions.

In multiple appeals over the past two decades, experts have produced evidence that Nikki suffered from undiagnosed pneumonia in the days before the fall, which progressed to the point of sepsis and caused her breathing to become depressed. They were also prescribed medications that are no longer given to babies.

At a recent legislative hearing, A juror in Roberson’s trial He said he would not have convicted Roberson if he had been presented with all of Nikki’s medical records, including the CT scan and toxicology report. Meanwhile, Governor Greg Abbott and Attorney General Ken Paxton Claiming Roberson’s guilt and that the case has already been properly decided.

Why a Texas House committee sued: Committee members said they called Roberson to testify after hearing expert testimony about Texas’ 2013 junk science law; This law allows courts to overturn a conviction if the scientific evidence at the heart of the case is discredited. Roberson tried but failed to use the law to win a new case.

After the House committee issued the subpoena, it obtained a temporary restraining order from the Travis County civil court to stay Roberson’s execution. Paxton then filed a petition with the Criminal Court of Appeals on behalf of TDCJ, asking the state’s highest criminal court to vacate that decision because the civil court lacked jurisdiction over the matter. The appeals court ruled in Paxton’s favor.

But the House committee responded by filing an emergency appeal to the Texas Supreme Court, the state’s highest civil court. The House argued that the Court of Criminal Appeals did not have jurisdiction over the case because the subpoena was a civil matter. The Supreme Court issued an interim injunction to stay the execution and asked both parties to file legal briefs before making the final decision.

What the state says: Paxton argues that the court’s decision forcing the state to stay a lawfully imposed sentencing order “contradicts the separation of powers.”

“The relief sought by the House Committee here usurps the Governor’s prerogative to grant a thirty-day reprieve in a death penalty case,” Paxton’s office writes in a legal brief. “The specific powers the Constitution grants to the CCA and the Governor with respect to criminal convictions and temporary stays, respectively, thus necessarily trump any general subpoena power.”

What the parliamentary committee says: Lawmakers, including committee Chairman Joe Moody, D-El Paso, and committee member Jeff Leach, R-Plano, allege Paxton’s office prevented TDCJ from complying with the subpoena and allowing Roberson to testify. They say issuing the subpoena does not assume another branch’s powers because Roberson’s execution was only temporarily stayed and lawmakers are constitutionally allowed to hear testimony to inform policymaking.

“Given the disagreement over some of the facts in the Roberson case, the Committee considered it necessary to hear him in person to decide his credibility as a witness,” council members said in a legal briefing.

Wider impact: The state supreme court’s decision in this case is unlikely to directly impact whether Roberson will be granted a new trial because that decision will be made by a criminal court. But this could have repercussions on the Legislature’s subpoena power. And his testimony in the case of a death row inmate at the State Capitol will be historic.

Three of the five Supreme Court Criminal Court judges who allowed Roberson’s execution to be postponed in January will no longer be on the court. If Roberson’s case somehow returns to court and any of the new justices take a different stance, the vote could swing in Roberson’s favor.

The court’s decision will also answer a new legal question about whether a lawful subpoena or execution order takes precedence.

“I think what we’re seeing is checks and balances of different branches of government, which is the constitutional vision in the United States, and it’s been largely replicated in Texas,” said Marc Levin, chief policy counsel for the Criminal Justice Council. “It’s healthy for that to happen.”