Chemical castration is the process of administering anti-androgen drugs to a male in an effort to reduce his testosterone levels and suppress his sex drive. Unlike surgical castration, in which the male's testicles are removed, chemical methods can be reversed by discontinuing use of the drugs. This process is used in many countries on convicted sex offenders, such as pedophiles or rapists, and in some places, it has reduced the chance of a repeat offense from 75% to 2%.
Although other drugs are sometimes used, medroxyprogesterone acetate (MPA) and cyproterone acetate are among the more common choices for chemical castration. MPA is the active ingredient in Depo Provera, a birth control drug that has become a popular anti-androgen because it only needs to be administered at three month intervals. All of these drugs lower testosterone levels in men, which leads to a decline in sex drive and can reduce their ability to become sexually stimulated. A reduction in testosterone can also lessen aggression in men, making them more compliant and less of a threat to others.
Proponents of chemical castration cite studies showing reduced recidivism rates as a major reason to continue use of the process. Arguing that it is more ethical than long term imprisonment, they also claim there is a danger in sentencing criminals to prison untreated. They fear that the sexual desires, fantasies and rage of criminals will build during their incarceration, while also providing them the time to plot new ways to commit their crimes undetected upon their release. Those in favor of chemical treatment also contend that it is humane when compared to surgical castration.
Opponents have concerns regarding the constitutional rights of criminals as well as the temporary nature of anti-androgens. The American Civil Liberties Union (ACLU) has stated their dissatisfaction with allowing judges rather than medical professionals to order medical treatment. They feel it is unconstitutional to force someone to accept medical treatment, particularly when those people run the risk of developing harmful side effects, like the development of osteoporosis due to diminished bone density, as well as cardiovascular disease that can result from an increase of body fat and a loss of muscle mass. Men may also see an increase in their breast size or a reduction in body hair as a consequence of continued anti-androgen use.
Chemical castration also interferes with the ability of men to procreate and therefore opponents argue that it is at odds with the right to privacy implied in the United States Constitution. For all these reasons, the ACLU believes the practice is cruel and unusual punishment and prohibited under the 8th amendment to the U.S. constitution. Opponents also contend that it does nothing to treat the underlying causes of sexually deviant behavior. As such, once a man stops taking the medication, he is inclined to revert back to criminal behavior. They believe that any treatment for sexual offenders must include psychological counseling in order to be truly effective.
Although the United States has used MPA to treat sexually deviant behavior since 1966, the Food and Drug Administration has never approved the drug for that purpose. California was the first state in America to legislate using anti-androgens as punishment for convicted sex offenders, but at least ten other states have followed suit. The use of chemical castration spans the globe, including the United Kingdom where it was used in the 1950s to attempt to cure people of homosexuality. Germany has employed the use of anti-androgens since the 1960s and, after the turn of the millennium, Israel, Poland and South Korea have all legalized the practice.