28/12/2011 07:26 GMT | Updated 28/12/2011 08:54 GMT

Stephen Lawrence Murder Trial Jurors Told 'Sympathy Has No Part To Play' In Decision

Jurors in the trial of two men accused of the murder of Stephen Lawrence have been warned not to let emotion influence their deliberations.

Justice Treacy told the panel at the Old Bailey that they must weigh up the evidence in the case without letting anger or sympathy play a part in the verdict.

"Emotion such as sympathy for the Lawrence family has no part to play," he said. "Equally, anger at the nature of the attack on Stephen Lawrence cannot guide your decision."

He told the jurors that they must be "sure" of any verdict they come to, and warned them that it would be unrealistic to expect every loose end to be tied up.

"It's not necessary for every question raised in a case to be answered or for every loose end to be tied up. This is real life, it's not a detective novel," they were told.

Gary Dobson, 36, and David Norris, 35, both deny murder.

During his summing-up, the judge set out key steps that jurors will need to follow in their route to a verdict.

These included considering whether forensic evidence found on clothes seized from Dobson and Norris's homes got there via contamination during handling and storage, as the defence argues.

The panel must also consider whether the defendants were present at the time of the attack and participated in it.

If at least one member of the group intended to kill or cause serious harm to Mr Lawrence, then the attackers would be guilty of murder, the judge said.

But if they intended to cause injury falling short of serious bodily harm, then the group would be guilty of manslaughter.

Justice Treacy said: "Manslaughter is an alternative verdict to murder but it should only, and I stress that word, be considered if you have found the defendant in question not guilty of murder."

He then went through the various witness accounts that the jury has heard, including details of any description of the attackers that they gave.

There were some differences in the account given by Mr Lawrence's best friend Duwayne Brooks and the other witnesses - he said he had been chased by one of the attackers.

The judge said the contrasting accounts could be because Mr Brooks felt "a subconscious need to justify himself for running off at the time that he and Stephen were attacked".

The court then heard a detailed account of the handling of exhibits, including assessments previously given by expert witness Rosalyn Hammond as to the risk of contamination.