Singapore is open to considering chemical castration as a possible measure to tackle sex crimes if there is clear evidence that it can reduce offending, Senior Minister and Home Affairs Minister K Shanmugam said on Sept. 8.
However, he noted that evidence on whether the treatment can reduce reoffending remains inconclusive.
Chemical castration is already used in some countries as part of the criminal justice system for certain people convicted of sex crimes. But how it is used varies depending on the country.
What is chemical castration?
Chemical castration involves medication that reduces the production or effects of sex hormones such as testosterone. This can lower a person’s sexual drive.
The effects are generally reversible, although permanent effects can occur in rare cases.
It is different from surgical castration, which involves removing the testicles.
While chemical castration is also used medically to treat certain cancers, some countries use it in criminal justice settings with the aim of reducing the risk of sexual reoffending.
The idea is that lowering sexual drive could help some offenders manage excessive or compulsive sexual urges.
Which countries use it?
Several countries allow chemical castration for certain sex offenders, although the rules differ.
South Korea, Indonesia and Kazakhstan allow compulsory treatment in some cases. South Korea introduced chemical castration in 2011 for certain offenders convicted of sexual crimes against minors and later expanded its scope.
Indonesia allows the treatment for some perpetrators of sexual violence against children, alongside clinical assessment and rehabilitation.
Poland allows compulsory treatment in certain cases, while Denmark, Germany and Sweden have allowed it voluntarily.
At least seven US states have laws allowing some form of chemical castration.
Thailand allows certain eligible offenders to choose the treatment. It can be considered when reviewing a reduced sentence or parole.
Does it reduce reoffending?
While chemical castration can lower testosterone levels and sexual drive, it is less clear whether those biological effects consistently lead to fewer sexual offences, according to CNA.
Some research has suggested that the treatment may reduce reoffending among certain offenders. British Justice Secretary Shabana Mahmood has also cited studies suggesting a reduction in reoffending.
However, this does not mean the broader evidence is conclusive.
Shanmugam said the evidence on whether chemical castration can effectively reduce crime remains inconclusive. Paul Cheong, a senior lecturer at the Singapore University of Social Sciences, has similarly said there is no conclusive evidence that lowering testosterone reduces sexual offending or reoffending among convicted sex offenders.
One concern is that not all sexual offences are driven primarily by sexual urges. Some may involve motivations such as power and control, meaning reducing sexual drive alone may not address the reasons behind the offending.
The treatment can also have side effects, including depression, weakened bones, reduced muscle mass and cardiovascular risks.
What would it mean for Singapore?
Introducing chemical castration would raise several legal questions.
Singapore’s sentencing system is based on four principles: deterrence, retribution, prevention and rehabilitation. Legal experts have questioned how chemical castration would fit within this framework.
There are also human rights concerns. Unlike imprisonment, the effects of treatment could continue after an offender has completed their sentence, depending on the medication and duration of treatment.
Singapore would also need to decide which offences and offenders would be eligible, given the wide range of sexual crimes and their varying severity.
Another question is who would decide when treatment is used and for how long: the courts as part of sentencing, or prison authorities after conviction.
For now, Singapore has not introduced chemical castration as a criminal justice measure. The government remains open to considering it if there is clear evidence that it can reduce sex crimes, but that evidence has yet to be considered conclusive.
