How did lethal injection become a widely used execution method in the United States?

Lethal injection became the most widely used method of execution in the United States primarily because it was perceived as a more humane and cost-effective alternative to existing methods like electrocution and the gas chamber.1

The state of Oklahoma first adopted the method in 1977, and Texas conducted the first lethal injection execution in 1982. Over the following decades, as states sought to move away from methods criticized for their brutality, lethal injection was adopted by the federal government, the military, and the majority of states where capital punishment remained legal.12

In 2008, the U.S. Supreme Court affirmed the constitutionality of the three-drug protocol in Baze v. Rees, characterizing it as a progression toward more humane execution practices. Despite this, the method has faced significant challenges, including drug shortages, the use of untested protocols, and reports of botched executions that have raised serious ethical concerns regarding the infliction of unnecessary pain and indignity on prisoners.12