Blameworthiness in both Action and Intention

Pharmacology Expert Witness
Blameworthiness in both Action and Intention

Blameworthiness in both Action and Intention

Actus reus means the “guilty act” which, if proved beyond reasonable doubt together with mens rea, “guilty mind”, generates criminal liability, because “the act is not culpable unless the mind is guilty”.

Expert Witness Pharmacology

A Guilty Mind

Actus reus and mens rea

A guilty act must be accompanied by some level of guilty mind for the crime to be constituted.

Crudely put: criminal liability is not incurred by an accused person acting with the absence of mental fault; it requires blameworthiness in both action and intention.

Accordingly, many defendants seek a defence under the mens rea rule, given that they have been listed for trial. They say that they lacked awareness of what they were doing, or acted under the adverse influence of [preferably prescribed] drugs.

Moreover, the general public is generally aware of the existence of drug interactions and / or side effects.

In consequence, this straw is sometimes clutched at by those in the legal deep water.

Causative or Coincidental?

Drug interactions often have a psychiatric element. Also, there are drugs which on their own sole account have their own psychiatric side effect profiles.

But although sometimes, psychiatric effects (from drugs either singly or in combination) genuinely cause pathological behaviour, there are other occasions in which pathological behaviour or criminal activity might simply be coincidental.

In short: is the effect causative or coincidental?

Adding to the already complex arena: it is possible for some psychiatric side effects, being unknown, to exert an unrecognised influence.

Furthermore, any underlying mental pathology is capable of either modulating a known side-effect, or simply causing aberrant behaviour including the misuse of drugs.

Example 1

The following case illustrates the difficulty in deciding whether an effect is causative of bad behaviour, or whether the bad behaviour is just coincidental.

Involved were serious sexual offences committed over a number of years which turned out to be coincident with the long term prescribing of psychoactive medicines including dihydrocodeine and Tuinal.

The male subject, however, was eventually recognised by consultant psychiatrists to have an element of depression, and was basically a malingerer who made a big issue of minor aches and pains – for which he was prescribed these “heavy duty” painkillers and hypnotic by his long-suffering medics.

There are known psychiatric side effects of dihydrocodeine and Tuinal. However, there were no significant drug-drug interactions identified, and although the time span and duration of prescription of both dihydrocodeine and Tuinal was the same as that covered by the offences, no causative link was defined.


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