Robert Wayne Williams was born on February 6, 1952, in the United States. Not much public information exists about his early life, childhood, or upbringing prior to his involvement in the fatal crime in 1979. He was known to be married at the time of the murder, and his wife was later implicated alongside him and their accomplice in the robbery.

Williams did not have a highly publicized criminal background prior to this incident, and there is no record of a prolonged history of violence or criminal behavior before 1979. However, his decision to engage in an armed robbery, alongside accomplice Ralph Holmes.

On January 5, 1979, Robert Wayne Williams and his accomplice Ralph Holmes carried out a violent armed robbery at the A & P Supermarket located on 3525 Perkins Road, in Baton Rouge, Louisiana. Both men wore ski masks and entered the store armed, with Williams carrying a 12-gauge sawed-off shotgun. Their target was the supermarket's funds, but the operation took a tragic and fatal turn.

As they entered, the store’s 67-year-old security guard, Willie Kelly, was near the front, helping bag groceries. Holmes approached him and attempted to grab Kelly’s sidearm from its holster. Sensing resistance or movement, Williams yelled “Don’t try it,” and immediately shot Kelly in the face at point-blank range, killing him instantly.

The pair continued the robbery after the murder. During the chaos, Holmes pistol-whipped a customer, and Williams accidentally discharged his weapon again, injuring two other individuals by shooting them in the feet. After the robbery, police were tipped off by an informant who identified Williams, Holmes, and Williams’ wife as participants in the crime. Arrests followed soon after. Williams and his wife later confessed, admitting their roles in the robbery and the murder.

Williams was convicted of first-degree murder and sentenced to death on May 30, 1979, by District Judge Frank Foil, after a jury found him guilty. Notably, Ralph Holmes, his co-defendant, was spared the death penalty and received a life sentence, likely due to his secondary role in the shooting.

During the trial, Williams maintained that the shooting had been accidental, claiming that he had no intention of killing Kelly. However, he chose not to testify in his own defense, and the court found the act intentional based on witness accounts and evidence.

In the aftermath, Police Chief Howard Kidder criticized the security company that had employed Kelly, highlighting that the guard had received no formal training and had been issued a substandard weapon. According to Kidder, proper training and equipment might have prevented the shooting.

Williams remained on death row at Louisiana State Penitentiary until December 14, 1983, when he was executed in the electric chair. He was pronounced dead at 1:15 a.m. and reportedly declined a last meal.