Martin had a paranoid personality disorder

But the fact is the Appeal Court judges decided Martin was suffering from diminished responsibility at the time when he shot Fred Barras with a pump action shotgun and wounded Brendan Fearon.

Evidence was called showing he suffered from a long standing paranoid personality disorder.

This had the effect of reducing Martin's conviction for murder to manslaughter, enabling the court to impose a substantially reduced sentence (life imprisonment is the only sentence for murder).

'Reasonable force'

Where does this leave those who wish to defend their property against burglars or a physical attack?

The general principle is that the law allows such force to be used in self defence as is reasonable, in the circumstances as the accused believed them to be.

Martin's farmhouse was rigged to deter intruders

It does not matter whether that belief, viewed objectively, or with hindsight, was "reasonable".

Significantly, even if the force used leads to a death it can still be "reasonable".

The test is therefore a simple one. It does have certain practical difficulties as juries are often asked to decide whether a defendant was using reasonable force some considerable time after the incident.

Effectively they need, in deciding on guilt, to get inside the head of the defendant and view the situation as experienced at the time.

In Martin's case, the trial took place over a year after the incident.

What Martin's case demonstrates is that force used in self defence has to be spontaneous.

Paul Gilbert, lawyer

Martin has always maintained he genuinely believed he was acting in self defence when he pulled the trigger that fired the fatal shot.

Public sympathy

Many who had been the subject of persistent burglaries, particularly in rural areas where police resources are stretched thin, have expressed sympathy for him.

What Martin's case also demonstrates is that force used in self defence has to be spontaneous.

The lengths to which he had gone to defend his property, rigging up ladders in trees as lookout posts and the removal of a stair inside his property did not assist him.

While it is right Martin's case does not add any further clarification in this area, the simplicity of the test is an advantage.

Every case has different facts and the more complicated the test, the harder is for juries to apply it - leading to inconsistency and injustice.

What Martin should not now be seen as, is the typical Englishman trying to defend his castle.