Alan Eugene Miller was born on January 20, 1965. Prior to the murders, he worked as a delivery truck driver in Pelham, Alabama.​

On August 5, 1999, Miller went on a shooting spree, killing three men: Lee Holdbrooks and Christopher Yancy at their workplace, and Terry Jarvis at a different location. Miller was apprehended the same day and subsequently convicted of capital murder in 2000, receiving a death sentence.​

After a failed lethal injection attempt in 2022 due to difficulties in establishing intravenous access, Miller was executed on September 26, 2024, using nitrogen hypoxia. This method involves replacing oxygen with pure nitrogen, leading to death by oxygen deprivation. Miller's execution marked the second instance of nitrogen hypoxia being used in the United States. Witnesses reported that Miller exhibited violent shaking and gasped for several minutes before being pronounced dead eight minutes after the procedure began. ​

The use of nitrogen hypoxia as an execution method has been controversial. Critics, including organizations like the American Veterinary Medical Association, argue that it is inhumane and unacceptable for euthanizing animals, raising ethical concerns about its application in human executions. Additionally, companies such as Dräger, a gas-mask manufacturer, have expressed opposition to their products being used in executions involving nitrogen gas.

Despite these concerns, Alabama officials defended the method's use. Attorney General Steve Marshall stated that Miller's execution delivered long-awaited justice for the victims' families.