Carl Wayne Buntion was born on March 30, 1944, in Harris County, Texas. He grew up in a difficult environment. His father was often violent towards the family. In one shocking incident, he murdered a man in front of one of his sons. The father's abuse affected Carl deeply. He experienced severe physical abuse, including injuries that resulted in broken bones. Carl later said he suffered from post-traumatic stress disorder because of the violence he witnessed and endured at home.

Carl had several siblings, including brothers. One of his brothers later served a twenty-year sentence for a different crime. The early years of Buntion's life were filled with fear and trauma, which would affect him throughout his life.

On June 27, 1990, Carl Wayne Buntion was a passenger in a vehicle that was stopped by Houston Police Officer James Irby. As Irby spoke with the driver of the vehicle, Buntion exited and shot Irby once in the head. Irby fell to the ground, and Buntion shot him twice in the back. After shooting Irby, Buntion fled the scene. He continued to fire at people nearby and attempted to carjack a driver. He also fired at another officer and held someone at gunpoint before being arrested in a nearby building.

In 1991, Buntion was found guilty of capital murder and sentenced to death. However, in 2009, the Texas Court of Criminal Appeals vacated his death sentence. Buntion was tried again in 2012, and his brother testified about their childhood. On March 6, 2012, he was once more sentenced to death.

Buntion's lawyers filed several appeals over the years. They asked the United States Supreme Court to hear his case, but in October 2021, the Supreme Court denied his appeal. In December 2021, they filed a state habeas application arguing that executing Buntion would be cruel and unusual due to his many years in prison and claimed he did not pose a danger to others. This application was dismissed. In March 2022, they requested a commutation of his death sentence, citing his age and health issues, but this request was also denied.

Buntion was scheduled for execution on April 21, 2022. A week before his execution, he contracted pneumonia. On the day of his execution, he suffered a head injury while being transported back to prison. Before his death, Buntion expressed remorse for his actions and stated he wanted the Irby family to have closure.

On April 21, 2022, Buntion was executed by lethal injection and was pronounced dead at 6:39 p.m. Prior to his death, he spoke to the warden and expressed his feelings. He was the oldest inmate to be executed in Texas at that time.