The execution of an Oklahoma death row inmate took place as planned at 6:00 pm on Tuesday. According to an Associated Press (AP) report, the inmate, Michael Hooper, had tried to escape his death sentence by challenging Oklahoma’s lethal injection process. On Tuesday the U.S. Supreme Court rejected Hooper’s request for a stay of execution. Hooper’s is the fourth execution to take place in Oklahoma in 2012.

Hooper was sentenced to death for killing his former girlfriend, Cynthia Lynn Jarman, and her two children, 5-year-old Tonya and 3-year-old Timmy, in December of 1993. According to the AP, Hooper shot each victim twice in the head and buried their bodies in a shallow grave on the outskirts of Oklahoma City.

According to the Oklahoma Department of Corrections website, the state switched to executing prisoners using a specific kind of lethal injection when Oklahoma’s method of old method of execution was ruled unconstitutional in 1972. The state has executed 176 men and three women since 1915. 82 of those executions were by electrocition, 96 were by lethal injection, and one federal prisoner was hanged.

(image)Oklahoma’s lethal injection method utilizes three executioners, each of whom administer one specific drug through intravenous lines in both of the prisoner’s arms. The first drug used is sodium thiopental or pentobarbital, which causes unconsciousness. The second is vecuronium bromide, which stops respiration. The third, potassium chloride, stops the prisoner’s heart.

Hooper’s family and the family of his victims watched the execution from behind windows in a viewing room adjacent to the execution chamber. The AP recounts that Hooper’s last words, spoken to family members, were, “I love you all.”

(Photos courtesy the Oklahoma Department of Corrections)