What effect does diabetes have on the criminal law (motoring)?


What is meant by diabetes?

Diabetes is a common chronic condition which currently affects three million people in the UK. It relates to the level of blood sugar in the individual’s blood and in certain cases can have a huge affect on the person.

Hyperglycemia versus hypoglycemia

Diabetes can be divided into either hyperglycemia or hypoglycemia.

What is the difference between the two?

Untreated diabetes is characterised by high blood pressure which is called hyperglycemia whereas diabetics on drug treatment where insulin is required to be taken can also suffer low blood sugar which is termed hypoglycemia. Hypoglycemia can cause effects which on the face of them are similar to alcohol consumption. Hyperglycemia can also cause similar mental impairment but to a lesser degree and with a much slower onset.

Diabetes and motoring offences

One of the main issues which can be affected by diabetes is dangerous driving. Accordingly drivers who are affected by diabetes must adhere to certain conditions.

The DVLA imposes strict conditions on diabetic motorists who must notify the DVLA of their condition and who are prohibited from driving Heavy Goods Vehicles (HGV’s). Furthermore, in order to reach the required visual standards all diabetic drivers of cars and motorcycles must recognise the symptoms of hypoglycemia and are issued with a detailed letter providing advice from the DVLA.

Most motoring accidents caused by drivers suffering with hypoglycemia

The risk of hypoglycemia – low blood sugar – is the main hazard to safe driving.

What is the reason for this?

The main reason for this is that it may endanger the life of the individual suffering from hypoglycemia as well of the lives of the other road users. Many accidents on the roads caused by hypoglycemia happen due to the driver continuing to drive even though they are experiencing warning signs of hypoglycemia. If an individual starts to experience warning signs of hypoglycemia whilst driving they must always stop as soon as is safely possible – if they do not it can often be fatal.

Are there any other offences which are often committed by individuals suffering from hypoglycemic episodes?

As well as offences caused by dangerous driving individuals suffering from hypoglycemia have also been arrested for certain public order and violent offences.

What does the criminal law say?

The forms of incapacity currently recognised by the criminal law of England and Wales are (sane) automatism and insanity – which includes insane automatism. The distinction between the two will depend on whether the cause is internal or external.

What must a defendant show to be able to plead automatism?

In order for a defendant to be able to plead automatism they must be able to show the following:

  • That they have suffered from a complete loss of voluntary control

  • That this was caused by an external factor – i.e. that he was not at fault in losing capacity

What must a defendant show to be able to plead insanity?

In order for a defendant to be able to plead insanity they must be able to show that there was a disease of the mind. A disease of the mind can include physical disorders such as diabetes as well as physciatric and neurological conditions, for example strokes and epilepsy.

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For more information on:

  • When then can an individual state that they should be absolved from criminal prosecution due to a hypoglycemic attack?
  • What is the difference between basic and specific intent?
  • How does this apply to the driving context?
  • When should a diabetic inform the DVLA of his condition?
  • What precautions should drivers who are required to take insulin follow when driving?