Parkinson’s, Pornography, and Pedophilia

If you developed Parkinson’s disease, you would no doubt be desperate for some relief from your symptoms. You would gladly take any medications that your doctor prescribed if they stopped you from shaking, shuffling, and freezing while you walked, and would be thrilled if those drugs were effective and you could move freely again. Nevertheless, the joy you felt might be tainted if you developed a known side effect of the medication: hypersexuality, or a dramatic increase in your sex drive and behaviour.

If your prescribed medication caused hypersexuality that led to criminal behaviour, should you be punished? Not according to the judges of two such cases, from the UK and Australia.

"Parkinson’s caused teacher’s child porn habit, judge rules" was the headline of a UK newspaper story in 2008. Philip Carmichael, a 58-year-old retired school principal, had been prescribed dopamine replacement therapy to relieve his Parkinson’s symptoms. During the period in which he took the medication, he downloaded 8,000 child pornography images.

Police also found one image on his computer that Carmichael had downloaded before starting this medication; Carmichael claimed he did not know where it came from. The existence of this single "pre-medication" image raises the question of whether the medication unmasked a latent or pre-existing tendency. The judge in Carmichael’s case disregarded this notion as this image was entirely separate from the bulk of the downloaded images.

Source: Andrew Baird

Judge Mary-Jane Mowat stated: "This is a very distressing case. To say that he was to blame would be a complete denial of the reality of the evidence that I see. He was not only an ill man at the time, but a man whose medication can be described as ultimately responsible for the committal of these offences."

There was a similar case of an Australian politician who developed hypersexuality after taking prescribed medications for his Parkinson’s disease. Over two years, Terry Martin spent approximately $150 000 on 162 different sex workers on 506 occasions and recorded details of his encounters on a spreadsheet. His sexual preferences expanded from his pre-medication heterosexuality to engaging with transsexual and male prostitutes.

Eventually, his hypersexuality led to criminal behaviours. He was found guilty of several criminal offences for having sexual intercourse with a person under the age of 17 years, and for producing and possessing child pornography. The judge in the Tasmanian Supreme Court case found a "direct causal link between the medication prescribed for Mr. Martin’s Parkinson’s disease and the offending… he would not have committed any crimes if he had not taken those drugs." Martin received prison sentences but they were suspended.

A critical question raised by these two cases is: did these men know that their medications could induce hypersexuality and, if so, how long did they know of this link before their illegal behaviours began? Did they continue to take their medications even while they knew about the side effects? Maybe they had been warned by their doctors and knew of the possible link, but had no reason to suspect that it would cause them to engage in criminal behaviour. Should they have foreseen those consequences?

There is plenty of evidence that dopamine replacement treatments can cause hypersexuality, but it is not clear if they specifically cause paedophilic interest, which occurred in these two cases.

The question of whether these medications can unmask a previously unexpressed sexual desire has also been raised, and a case reported in The Journal of Sexual Medicine suggests that this is possible.

Norman was 67 years old when an increase in the dose of one of his prescribed Parkinson’s medications (pramipexole) led to a profound change in his sexual behaviour. His wife reported that he suddenly wanted sex daily (after a previous once-a-week routine), and also developed an extreme preference for anal sex, and would vocalise "unusual obscenities" during it. He had never expressed this desire or requested this type of sex in over 40 years of marriage.

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Norman initially denied any changes to his doctor, but later agreed his requests were "unusual compared with his previous sexual experiences" with his wife. According to the case report, he said that "these were practices that he secretly desired when he was younger," and that "now he felt somehow less ashamed to put his desire into practice." After the pramipexole was ceased his sexual behaviour returned to its usual pattern.

Was Norman’s sudden interest in anal sex an authentic expression of the "real" Norman that the medication had "unmasked" and finally allowed him to express after decades of repression, or was this a de novo medication-induced desire that was not really him at all?

In the case of Philip Carmichael, did the single child pornography image that he downloaded before he started his medication constitute a "latent tendency"? It is impossible to know. Carmichael denied any knowledge of the pre-medication image. He had had an unblemished career as a school principal, and there were no previous reports of any paedophilic interests or behaviour, but only Carmichael knows his true self.

The judge in Carmichael’s case certainly did not believe his criminal behaviour reflected a previously hidden paedophilic interest. Carmichael’s own statement that the medication "turned him into a paedophile" suggests that his criminal behaviour did not reflect an unmasked latent tendency, but was something entirely foreign that became impossible to stop.

Some people who have experienced drug-induced hypersexuality in the context of Parkinson’s disease have received compensation. In December 2014, the pharmaceutical company Pfizer agreed to settle a class action brought by 160 Australian patients who had suddenly developed hypersexuality or pathological gambling after taking the drug Cabaser, a dopamine treatment for Parkinson’s disease.

In France, Didier Jambart received €197 000 (AU$240 300) in compensation from GlaxoSmithKline for taking the Parkinson’s disease drug ropinirole, sold as Requip, that transformed him into a sex and gambling "addict" and made his life "hell."

It is important to be aware that not everyone taking medications for Parkinson’s disease experiences a change in their sex drive or behaviour, and even if they do, it is rare that it is dramatic enough to lead to criminal behaviours and legal proceedings like those described here. I’ve highlighted these rare cases because they demonstrate the links between sex, our brains and the law, giving us insights into how legal systems are currently dealing with these incredibly complex issues.