In 1982, Hancock was charged with fatally shooting a drug trafficker, Charles Lester Warren, which he claimed was a killing done in self-defense, and he was subsequently given a four-year jail term for first-degree manslaughter.

19 years later, Hancock would commit the double murder of James Vincent Lynch III and Robert Lee Jett Jr. by shooting both of them to death in 2001, for which he similarly claimed were killings done in self-defense.

According to media sources and court documents, Hancock and his accomplice, 16-year-old Kenneth Ray Hulsey,[3] were involved in a shooting incident that left one man dead and two bystanders injured.

[10] On April 27, 2001, 19 years after his first killing, Phillip Hancock once again committed murder, and this time, he shot two men aged 38 and 58 respectively in Oklahoma City.

[13] In fact, he spent a year evading justice after he murdered Lynch and Jett before he was arrested and later convicted on March 26, 2002, for firearm and drug-related offenses, and incarcerated in the Great Plains Correctional Institution in Hinton.

[12] Hancock lost his final appeal to the U.S. Supreme Court in 2016, making him one of Oklahoma's 11 death row inmates eligible for execution,[16][17] and the number increased to 16 as of March 2018.

Six other condemned prisoners – Jemaine Cannon, Anthony Castillo Sanchez, James Ryder, Michael Dewayne Smith, Wade Lay and Richard Glossip – also had their execution dates rescheduled between 2023 and 2024.

[26] Assistant Attorney General Joshua Lockett rebutted the defense's arguments, stating that the self-defense claims did not tally with the objective evidence found at the crime scene and Hancock himself gave inconsistent accounts of what happened.

[27][28] The final decision laid at the hands of the Oklahoma state governor Kevin Stitt, who had the discretion to either grant or refuse clemency for Hancock.

Governor Stitt also rejected the parole board's recommendations for clemency in the two cases of Bigler Stouffer and James Allen Coddington, both of whom were, in the end, executed for murder.

Merely three hours after Governor Stitt refused to grant clemency, 59-year-old Phillip Dean Hancock was officially put to death via lethal injection at the Oklahoma State Penitentiary.

[36][37][38] Phillip Dean Hancock was the fourth and final condemned inmate to be executed in Oklahoma after Scott James Eizember (January), Jemaine Cannon (July) and Anthony Sanchez (September).

One focal point of criticism was that the Oklahoma state governor Kevin Stitt waited until the last minute before he announced his decision to not commute Hancock's death sentence and allowed the execution to move forward.

In response to the criticism, Governor Stitt released a media statement and expressed that he had duly considered the matter and relevant factors like Hancock's previous self-defense claims in the 1982 killing of Charles Warren.

On behalf of the families, Jett's brother Ryan told the press that justice was finally served 22 years after the double murder.