Carman L. Deck was born on August 9, 1965, and grew up in Missouri. His childhood was deeply troubled—he was raised in an unstable home environment marked by abuse, poverty, and neglect. Reports indicated that he spent time in foster care and juvenile detention facilities. Deck had a long history of criminal behavior before committing the double homicide in 1996. He had prior convictions for burglary and other crimes. Despite his difficult upbringing, his later actions would lead to one of the most legally significant death penalty cases in U.S. Supreme Court history.

On July 8, 1996, Carman Deck entered the home of James and Zelma Long, an elderly couple in De Soto, Missouri, with the intention of robbing them. Once inside, Deck forced the couple to lie face down on their bed, robbed them of cash and jewelry, and then shot both victims execution-style in the back of the head. He fled the scene, but investigators quickly identified him as a suspect. Deck was arrested on August 27, 1996.

His trial began on February 17, 1998. Three days later, on February 20, he was found guilty of two counts of first-degree murder, among other charges, and sentenced to death the next day. However, that was only the beginning of a long legal journey.

Deck’s death sentence was overturned multiple times due to procedural issues, including ineffective assistance of counsel and judicial misconduct related to visible shackling during sentencing. His case eventually reached the U.S. Supreme Court, resulting in the landmark 2005 decision Deck v. Missouri, where the Court ruled 7–2 that visibly shackling a defendant during the sentencing phase, without a specific and justified reason, violates the Due Process Clause of the Fifth and Fourteenth Amendments.

Despite several resentencing trials, Deck was ultimately re-sentenced to death. On October 19, 2020, his death sentence was reinstated by the U.S. Court of Appeals for the Eighth Circuit. His final execution date was scheduled by the Missouri Supreme Court on January 31, 2022.

On May 2, 2022, the U.S. Supreme Court denied Deck's final request to stay the execution. Missouri Governor Mike Parson declined to grant clemency. On May 3, 2022, Carman Deck was executed by lethal injection at the Eastern Reception, Diagnostic and Correctional Center in Bonne Terre, Missouri. He was pronounced dead at 6:10 p.m.