Alabama is planning to require convicted paedophiles to undergo chemical castration in order to be granted parole from prison, a controversial measure already in effect in several other US states.
The southern state's legislature passed a bill stipulating that any inmate aged 21 or over who was convicted of a sexual crime against a minor aged under 13 years must take medication to reduce their testosterone before they can be granted early release.
The treatment, which affects a person's libido, will continue until a judge rules it to be "no longer necessary."
If the person stops taking their medication, they will be returned to jail.
Aside from exceptional cases, the parolees will have to pay for the medication themselves, according to the bill, which has been sent to Republican governor Kay Ivey who has voiced her support for it.
"They have marked this child for life and the punishment should fit the crime," the bill's sponsor, lawmaker Steve Hurst, told local WIAT radio.
California introduced a similar measure in 1996, followed by several other states including Florida, Georgia, Iowa and Louisiana.
In Texas, convicted paedophiles can volunteer for actual surgical castration in an effort to secure parole.
The process has become the subject of scientific debate as to whether castration is actually effective in preventing sex crimes, underlining that the impulse is not entirely sexual but psychological.
Others have warned that chemical castration, while intended to be reversible, can have significant side effects, including on a person's physical appearance.
Some human rights advocates have argued that the life-long measure violates the constitutional ban on "cruel and unusual punishment."
The United States has also created a federal sex offenders register which lists everyone convicted of a sexual crime against a minor and is available online.
