John Ashley Brown Jr. was a resident of New Orleans, Louisiana. Details about his early life are limited, but by 1984, he was involved in drug use, specifically cocaine.

On the night of September 7, 1984, Omer Laughlin and his wife were returning to their car after dining at a restaurant near Dauphine and Touro streets in the Faubourg Marigny neighborhood of New Orleans. Around 11:45 p.m., as they approached their vehicle, a man emerged from a nearby car, confronted them, and demanded money. When Mrs. Laughlin screamed and fled to seek help, the assailant attacked Omer Laughlin, stabbing him 13 times. He succumbed to his injuries before assistance could arrive.

Shortly after the incident, Sergeant James Scott of the New Orleans Police Department noticed a vehicle matching the description provided by Mrs. Laughlin. Inside were John Brown and a woman named Anna Hardeman. Observing blood on Brown's arms and between his toes, as well as a shopper's card bearing Omer Laughlin's name on the car floor, Sergeant Scott arrested Brown. A subsequent search revealed Laughlin's wallet and a concealed Bowie knife under the passenger seat.​

Brown was indicted for first-degree murder. During his trial, the jury found him guilty and recommended the death penalty. Judge Patrick Quinlan sentenced him to death. Anna Hardeman, initially charged alongside Brown, later pleaded guilty to being an accessory after the fact and received a five-year prison sentence.​

After spending 12 years on death row at the Louisiana State Penitentiary, Brown was executed by lethal injection on April 24, 1997. His case was notably featured in the 1998 documentary "The Farm: Angola, USA," which provided an in-depth look at life inside the prison and included interviews with Brown leading up to his execution.​