THE jury in the Jock Straiton murder trial has retired to consider its verdict.

The nine men and three women are now charged with deciding whether Paul Blower, Nigel Goolding and Joshua Spruce are guilty of murder, guilty of manslaughter, or acquitted.

Judge Roderick Evans said each defendant must be considered separately and separate verdicts must be given for each one.

The prosecution allege the three took part in a ‘joint enterprise’.

If the jury accept this then each man is responsible and can be held accountable for the actions of the others, even if the part they played was only a minor one.

A ‘joint enterprise’ can be planned months in advance or can be a spur-of-the-moment agreement between two or more people to carry out a crime.

Judge Evans said: “A wink, a nod or a knowing look can be sufficient to form a plan or agreement.

“The mere presence of someone cannot make a person guilty. The fundamental issue is whether the defendant was party to inflicting violence on Jock Straiton.

“However, if a defendant does something different to what has been planned, his actions will be considered outside of the joint enterprise.

“The prosecution say that all the violence used was within the scope of this joint enterprise and if you are sure that that is correct then the fact each played a different part would not matter.”

To convict for murder, jurors were advised they must be sure that the killing was unlawful, that the defendants were somehow involved in it, and that the intent was to cause death or very serious injury.

But Spruce and Goolding have argued that neither meant to cause serious harm and simply hit out in self-defence. They say their actions were not part of a joint enterprise and they are therefore not responsible for Mr Straiton’s other injuries.

Blower said he did not use any violence himself and did not intend to kill or injure Mr Straiton, nor was he party to any plan to do so.

Advising the jury Judge Evans said: “It is agreed that Jock Straiton was killed by his injuries but for which injuries does the defendant bear the responsibility?

“The use of force or violence on another is unlawful.

“Being annoyed or wanting revenge cannot make force lawful.

“But it is common sense that a person, who is attacked or believes he is about to be attacked, may use such force as is necessary to defend himself.

“Did the defendant honestly believe that it was necessary to defend himself? Someone who overreacts and turns it into a punitive attack would not be acting lawfully.

“But bear in mind that in the heat of the moment a person cannot be expected to judge how much force is necessary.”

If all elements of murder are proved, jurors must consider if the partial defence of provocation can be applied, which would reduce the charge to manslaughter.

In legal terms, it means something is done by another, in this case Jock Straiton, which could cause someone to suddenly and temporarily lose his or her self-control.

Jurors were given a four-question plan to help reach a verdict: 1 - Are you sure that the defendant used or was party to a joint enterprise to cause some bodily injury? If no, then verdict must be not guilty.

2 - Are you sure the blow or blows to Jock Straiton’s head which caused the fatal injuries were delivered by the defendant or were not different from the expected level of violence of the joint enterprise? If no then verdict must be not guilty.

3 - Are you sure the defendant intended to kill or cause serious injury or that either were expected as a result of the joint enterprise? If the answer is no, then the defendant should be found not guilty of murder but guilty of manslaughter. For Blower if the answer is yes then he should be found guilty of murder. For Spruce and Goolding, who admit to using some degree of violence, the next question must be considered.

4 - Are you sure the defendant was not provoked? If the answer is no then the defendant is guilty of manslaughter, if yes then he is guilty of murder.