Should PMS be a legal defence?

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Woman by the sea water

Premenstrual syndrome, or PMS, is sometimes blamed for female behaviour that may otherwise be considered inexcusable. Thousands of jokes surround the topic, and the syndrome has even been used in court to successfully defend criminal charges.

But is PMS really the culprit? And should it be a valid legal defence?

The history of PMS in court

UK courts are not strangers to PMS. From the 1950s onward, PMS has been used as a defence, or a mitigating factor, for offences ranging from shoplifting to murder.

One such case, decided in England in the early 1980s, concerned barmaid Sandie Craddock.

Ms Craddock had many prior convictions and, in a fit of rage, killed a fellow barmaid.

Combing through her lengthy criminal history, it became apparent that something happened to Ms Craddock that “turned her into an animal each month and forced her to act out of character”.

The argument, of course, was that PMS caused her to act out of character. As a result of that submission, Craddock was found ‘not guilty’ of murder but guilty of manslaughter due to diminished responsibility. She was placed on court-ordered progesterone.

Other countries

The UK is not the only place where PMS has been raised during criminal trials.

One woman in the US successfully avoided a drink driving conviction due to her lawyer’s argument that PMS had aggravated the effects of the alcohol.

And in a Canadian case, the defendant’s psychiatrist was willing to categorise her as legally insane due to the effects of PMS – and therefore not capable of murder.

Australian courts have never seen PMS as a defence or partial defence; in other words, something that disproves a defendant’s guilt, or reduces a charge of murder to manslaughter.

However, PMS has been raised as a mitigating factor in Australian courts. A ‘mitigating factor’ is something that is taken into account during the sentencing process and can result in a more lenient penalty.


Several studies during the 1970s and 80s suggest a link between females offending and PMS. They essentially found that more offences were committed during a female’s premenstrual week than at any other time of the month.

So does this mean that PMS is responsible for many offences committed by females?

And equally, can high levels of testosterone be blamed for violence by men?

Let’s take a quick look at how the defences of mental illness and diminished responsibility work:

Mental capacity to commit a crime

In order to be found guilty of a crime, a defendant must first have the mental capacity to understand their actions. This has been recognised for some time in our legal system, and it is well accepted that people who do not have the requisite mental capacity do not belong in the courts.

Accordingly, those who are mentally ill may be diverted into programs where they can receive the treatment they need.

For some, the prospect of PMS as a defence was welcomed – many women who suffered from severe PMS felt relieved that they were suffering from something that was recognisable and ‘real.’

However, amongst criminal defence lawyers in Australia, it appears to be generally accepted that PMS does not make a woman insane.

It is also generally recognised that PMS occurs on a spectrum – some women will experience few if any symptoms, while others will be seriously affected.

Symptoms of PMS can include anxiety, irritability, tension, abnormal social interactions, rapid mood changes and depression – but insanity, even temporary, does not appear to be one of them. And symptoms on the most severe side of the scale will only be experienced by a small percentage of women on a regular basis.

Diminished responsibility

As mentioned, a person must have the requisite mental capacity in order to be guilty of an offence, but of course there is no clear line between so-called ‘insanity’ and certain acute mental health conditions. As a result, the partial defence of diminished responsibility emerged.

Diminished responsibility is distinct from a complete lack of capacity but will affect a person’s ability to make rational judgments as well as to control their actions in accordance with these rational judgments.

Diminished responsibility has been replaced in NSW with the partial defence of “substantial impairment by abnormality of the mind.” Abnormality of mind means that the state of mind of the defendant must be so abnormal that a reasonable person would classify it as such.

A defendant’s responsibility does not need to be destroyed altogether – but it must be “substantially impaired”.

Problems with PMS as a defence

The use of PMS as a defence has attracted many critics – including sceptics who claim it is too easy to fake, and feminists who argue that any defence which implies that a woman turns “into an animal each month” is incredibly offensive and damaging to women in general, and can imply that women are weak-willed and irrational.

At the same time, there is an argument that if PMS can be used as a defence for women, then men should be allowed to use evidence of high levels and fluctuations in testosterone as a defence against violent crimes such as assault and murder. The argument is that both PMS and male aggression are linked to hormones – and that to refuse evidence of levels and fluctuations of a hormone that is linked to aggression (testosterone) when fluctuations in female hormones are being used as a defence is unfair; or to put it another way, ‘what’s good for the goose is good for the gander’.

But would it be acceptable for a man to justify, for example, bashing a woman because his testosterone levels were high?

The feminist perspective

In 1981, Deborah Wardley fought to overcome sexism and get a job as a pilot.

Wardley went to the Australian High Court to argue against Ansett’s discrimination against female pilots. She submitted that the airline refused to hire her as a pilot because her menstrual cycle would make her unsuitable.

From a feminist perspective, it might be argued that any defence which seeks to imply women are incapable of rational thought is inherently demeaning – and would be a step backwards in the fight for equality. In other words, implying that some women lack capacity each month to the point where they are not responsible for their actions may be damaging to women in general.

PMS into the courtroom is therefore a double-edged sword – perhaps appearing at first to be a positive step towards recognising the reasons behind female offending, but doing more harm than good to women in the long run.

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Ugur Nedim

Ugur Nedim

Ugur Nedim is an Accredited Criminal Law Specialist with 25 years of experience as a Criminal Defence Lawyer. He is the Principal of Sydney Criminal Lawyers®.

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