The two most commonly accepted and implemented forms of capital punishment are the gas chamber or lethal injection.
In the late eighteenth century, opposition to capital punishment garnered enough strength to lead to important restrictions on the use of the death penalty in several northern States, while Michigan, Rhode Island, and Wisconsin abandoned capital punishment altogether. Likewise, in 1794, Pennsylvania adopted a law differentiating the degrees of murder and only used the death penalty for first-degree murder (i.e., premeditation). In 1846, Louisiana abolished capital punishment and authorized the option of sentencing a criminal to life imprisonment rather than death. While public executions stopped occurring after the 1830s, they did not completely end until after 1936.
In 1972, the death penalty was abolished by the United States Supreme Court in the landmark case of Furman v. Georgia. The primary reason that the United States Supreme Court declared capital punishment to be unconstitutional was that it violated the Eighth Amendment's prohibition against cruel and unusual punishment. However, the United States Supreme Court later reversed its position in Gregg v. Georgia, stating that capital punishment did not violate the prohibition against cruel and unusual punishment. Since the death penalty was reinstated, 38 states currently allow individuals to be executed. Lethal injection is the most common method utilized in executions.
The arguments in opposition to capital punishment involve a multitude of cultural, economic, environmental, ethical, legal, moral, philosophical, political, practical, religious, social, and sociological theories. Proponents of the death penalty argue that executing murderers and other serious offenders will dissuade others from committing such heinous crimes. However, "[a]ll the evidence taken together makes it hard to be confident that capital punishment deters more than long prison terms do.