Grayson’s three accomplices managed to escape execution because they were under 18 at the time of Deblieux’s murder

An Alabama inmate found guilty of murdering a hitchhiker 30 years ago on Thursday became the third person in America to be executed using nitrogen gas, furthering the ongoing debate about whether the method is an inhumane way to carry out death penalty sentences.

Carey Dale Grayson is set to die by nitrogen hypoxia after being convicted of killing 37-year-old hitchhiker Vickie Deblieux in 1994.