While some states eliminated the death penalty in the mid-nineteenth century, it was the first half of the twentieth century that marked the beginning of the Progressive Period of reform in the United States. From 1907 to 1917, six states completely outlawed the death penalty, and three limited it to the rarely committed crimes of treason and first-degree murder of a law enforcement official. These reforms did not last long. There was a frenzied atmosphere in the United States, as citizens began to panic about the threat of revolution in the wake of the Russian Revolution. In addition, the United States had recently entered World War I, and there were intense class conflicts as socialists mounted the first serious challenge to capitalism. By 1920, these circumstances led five of the six abolitionist states to return to capital punishment.
In 1924, the use of cyanide gas was introduced in the state of Nevada as a more humane way of execution. Gee Jon was the first person executed by lethal gas. The state tried to pump cyanide gas into Jon’s cell while he slept, but this proved impossible, and the gas chamber was constructed.
From the 1920s to the 1940s, there was a revival in the use of the death penalty, due, in part, to the writings of criminologists, who argued that the death penalty was a necessary social measure. In the United States, people were suffering through Prohibition and the Great Depression. There were more executions in the 1930s than in any other decade in U. S. history, an average of 167 per year.
In the 1950s, however, public sentiment began to turn against capital punishment. Many allied nations either abolished or limited the death penalty, and in the U. S., the number of executions dropped dramatically. Whereas there were 1,289 executions in the 1940s, there were 715 in the 1950s, and the number fell even further, to only 191, from 1960 to 1976. In 1966, support for capital punishment reached an all-time low. A Gallup poll showed support for the death penalty at only 42 percent.