It’s called Medication to Manage Problematic Sexual Arousal. The short name is MMPSA. Pick up on the story Thousands of sex offenders in England and Wales could get libido-suppressing drugs | Prisons and probation | The Guardian . This does not mean, 'I’m ‘a Guardian reader’ - just in case.
[Declaration of interest: I am recognised as a Human Rights Defender by Amnesty International. That does not mean I am in liaison with Amnesty International or represent their views. I act independently.]
Unfortunately it is not possible to airbrush politics out this, so as to stay totally focused on the interface of law and medical practice. Why? Those who were around in the days of DSPD will understand. I can’t go back into all of that now. In a nutshell politics - as per DSPD directions - ruled where statute could not be passed.
So watch this new space for DSPD 2.0 in a manner of speaking.
For those who are unaware, psychiatrists will be called upon to medicate patients (who are sex offenders), in certain institutional domains. This may unfold over the next 3 years or so.
The MMPSA pilot is expanding across England. The Government is also exploring whether treatment could be made mandatory or incentivised. This raises hard questions about consent, bodily autonomy and state power.
By July 2026 the Government said it was exploring mandatory or incentivised treatment. Mandatory and incentivised? How will that work in the area of full and free capacity assessments? I don’t know the answers.
Treatment was piloted at HMP Whatton in 2007 and developed slowly. Because HMP Whatton’s long-term dataset proved successful, the research transitioned from a localised evaluation to an expanded national ethical framework across multiple UK prisons.
Further, the HMP Whatton MMPSA dataset was considered successful for demonstrating an approximate 30% reduction in sexual compulsivity scores and enabling engagement in therapy. Clinical evaluations showed effectiveness in managing problematic arousal. This did not prove a definitive reduction in long-term reoffending. The study is limited by small sample sizes, lack of randomised controls, and a focus on in-custody behaviour, as noted by the Ministry of Justice. A multi-site randomised trial is currently underway to address these limitations by 2028.
At present, no statutory regime compels people to take anti-libidinal medication. The legal framework may unfold in time.
If treatment helps the patient and the public, there is no conflict of interest. The problem starts when 'Dr State’ does more than offer treatment.
Making treatment mandatory could mean many things. Could we see: forced medication despite refusal or acceptance as a condition of release, or required attendance with the right to refuse, or maybe treatment staying voluntary while refusal affects parole?
Voluntary treatment for carefully selected people is one thing. Using medication as a tool of statutory power another. But as we saw in DSPD, statute was not required.
The question is not whether medication reduces sexual arousal. The question is whether treating ‘a mechanism’, in a person, will materially reduce the probability that the person re-offends.
The government is politically enthusiastic because MMPSA offers a clinical mechanism to mitigate risk in a heavily congested prison system. However, criminologists and clinicians are much more scientifically cautious. They have emphasised that medical treatment pathways should not be operationalised to solve a prison problem.
There is a risk of dehumanisation in the gallop. Eternal vigilance is needed. This Anti-libidinal Interventions and Human Rights | Human Rights Law Review | Oxford Academic is a recommended good read.