FELICIA ANNE GAYLE PICUS was found dead in her home, the victim of a vicious murder that devastated her family and rattled her neighbors in the gated community of University City, Missouri, just outside St. Louis. Police suspected a burglary gone wrong. The scene was replete with forensic evidence: There were bloody footprints and fingerprints, and the murder weapon — a kitchen knife used to stab Picus — was left lodged in her neck.

That detail caught the medical examiner’s attention. Weeks earlier, another woman had been stabbed to death just a couple of miles away, and the weapon was left in the victim’s body. Days after Picus’s murder, the University City police chief told the St. Louis Post-Dispatch that investigators had identified a “prime suspect,” someone they said had been spotted in the area “in recent weeks,” whom they believed had killed before.

But whatever became of that lead is unclear. After Picus’s family posted a $10,000 reward for information leading to the arrest and conviction of her killer, a jailhouse informant named Henry Cole came forward with a story about how his former cellmate, Marcellus Williams, had confessed to murdering Picus. Soon, police secured a second informant: Laura Asaro, Williams’s former girlfriend, also told the cops that Williams was responsible for the killing. There were reasons to be wary of their stories. Both informants were facing prison time for unrelated crimes and stood to benefit. Many of the details they offered shifted over the course of questioning, while others did not match the crime. Nonetheless, Williams was charged with Picus’s murder, convicted, and sentenced to death.

Questions about the investigation and Williams’s guilt have only mounted in the years since the August 1998 crime. DNA testing on the murder weapon done years after his conviction revealed a partial male profile that could not have come from Williams. On the eve of Williams’s scheduled execution in 2017, then-Missouri Gov. Eric Greitens intervened. He issued an executive order that triggered a rarely used provision of Missouri law, empaneling a board to review the evidence, including DNA, that jurors never heard about at trial.

While that review was ongoing for most of the last six years, the board never submitted a final report or recommendation to the governor, as the law requires. Instead, last June, Gov. Mike Parson announced that he was rescinding his predecessor’s order, effectively dissolving the panel that had been reinvestigating the case.

The question now is whether Missouri law allows the governor to simply disappear an ongoing investigation. Because the law has so rarely been used, its contours have never been fully litigated, prompting the Midwest Innocence Project, which represents Williams, to file a civil lawsuit seeking to invalidate Parson’s order. The state’s attorney general balked, arguing that Williams was trying to usurp the governor’s independent clemency powers. The AG has asked the Missouri Supreme Court to toss the lawsuit — and clear the way for Williams’s execution.