Tennessee Gov. Bill Lee appointed a renowned former US attorney to lead the independent probe into the botched execution of death row inmate Christa Pike — hours after the state’s prison chief resigned Saturday.

Ed Stanton, who served as the US attorney for the Western District of Tennessee from 2010-17, will review the state Department of Correction’s conduct during Pike’s execution attempt to determine whether protocol was followed, the Republican governor’s office announced.

Stanton previously led an independent investigation into the state’s lethal injection protocol in 2022 after Tennessee officials uncovered that drugs used in prior executions weren’t being tested properly, WKRN-TV reported.

The revelation led Lee to halt all executions in Tennessee for the remainder of 2022 — including capital punishment for death row inmate Oscar Smith — and for the nearly three years that followed.

Stanton’s review pushed Tennessee officials to “substantially rewrite the protocol before executions resumed” in February 2025, the governor’s office said.

The new lethal injection protocol introduced a single dose of pentobarbital — the same drug administered to Pike on Wednesday — instead of a three-drug cocktail that included a paralytic agent. 

The new protocol was established by Tennessee DOC Commissioner Frank Strada, who announced earlier on Saturday he was stepping down from his position in the aftermath of Pike’s botched execution.

Pike — who was convicted of brutally killing a teen classmate in 1995 — is still alive, but is unconscious, intubated and breathing through a ventilator, according to her lawyers.

The newly-resigned Strada said he continues to “believe the Department carried out its responsibilities in accordance with the established protocol.

But he welcomed the independent review, calling it “entirely appropriate and necessary” and adding, “I look forward to doing everything I can to help determine exactly what occurred,” according to WKRN.

Stanton’s review will also consider if additional recommendations are necessary to ensure the protocol “continues to be lawful and effective,” according to Lee’s office.

A group of Tennessee death row inmates sued the state after the single-use lethal injection was announced in December 2024, citing concerns that the protocol amounted to a constitutional violation.

Anti-death penalty advocates were also among those concerned with the new protocol and pointed out the federal government no longer conducted lethal injections through a single dose of pentobarbital, apparently because it was unclear whether the lethal drug caused unnecessary pain and suffering, WKRN reported.

Although Lee’s announcement comes just days after Pike — the first woman set to be put to death in Tennessee in over 200 years — received two doses of the lethal injection and survived, the state botched another execution earlier this year.

Convicted murderer and kidnapper Tony Carruthers was set to be put to death by lethal injection in May, but Lee halted his execution and received a one-year reprieve after prison officials failed to find a vein to establish a backup IV in accordance with the protocol.