I have been unable to find very much information related to chemical castration and would like some more information. This man has not been declared legally incompetent and will have to consent to using Depo-Provera. Any assistance you could provide would be appreciated. Provera reduces testosterone levels in males, and may also compete with testosterone for receptors in the brain. This may help reduce violent sexual fantasies, as well as reduce the actual behaviors.
Side effects can include weight gain and increased blood pressure.
You can find good discussions of this agent in the article by Gottesman and Schubert, Journal of Clinical Psychiatry 1993, vol. The Gottesman article also has numerous references.