A prosecutor urged the Court of Appeal to uphold the conviction of Kevin Warner due to “overwhelming evidence” that he was guilty of murdering Dekimo ‘Purple’ Martin.Deputy Director of Public Prosecutions Carrington Mahoney was presenting his case a day after defence lawyer Elizabeth Christopher argued the conviction is “completely unsafe”Ms Christopher told the Court of Appeal that the jury in Warner’s trial should never have heard “extremely prejudicial” evidence about gangs.Warner, 22, was convicted last year and jailed for a minimum of 35 years for shooting Mr Martin in the back at the victim’s home.Witnesses told at Warner’s trial he was a close family friend of the 24-year-old victim and the last person seen talking to him before he was shot on the night of May 28 2010. No motive for the killing has ever been given.Launching the appeal on Monday, Ms Christopher argued that photographs and testimony from gang expert Sergeant Alex Rollin should not have been put before the jury. Sgt Rollin named Warner as an associate of the White Hill Crew and his brother, Kavon Hart, as a member of the Money Over B*****s (MOB) gang.According to Ms Christopher, the White Hill Crew “is not a gang known for shooting people” like the MOB is, and Warner was not in the MOB.She also complained about photographs downloaded from Mr Hart’s phone, which showed him with a young child holding a gun. Another showed a neck chain with the MOB acronym. A third showed Mr Hart making a gang sign with his hands.“It’s our submission that the evidence was highly prejudicial,” said Ms Christopher on Monday.“It’s a photograph of someone having a child hold a gun. It’s very prejudicial, indeed it beggars belief.”Warner admitted during the trial that his brother kept a gun at his house. However, according to Ms Christopher, the jury heard no evidence that Warner borrowed or used that gun.Mr Mahoney said yesterday that the photo of the child was in fact used by prosecutors to show the jury the best pictures they had of the gun.He explained that firearms expert John Kirkpatrick looked at the photographs and said it appeared to be a real 9mm semi-automatic pistol. Another expert, Dennis McGuire, said it was similar to the type of gun used in the murder. The trial heard it was also used by the MOB in other crimes after Warner was arrested over the murder.Mr Mahoney stressed that the photographs were chosen to demonstrate the gun at the best possible angles for the jury and “it just happened that the child was holding it”.Court of Appeal judge Sir Austin Ward noted that the scene depicted in the disturbing photograph appeared to show an offence being committed under the Children Act. Mr Mahoney assured the court that he invited “the relevant departments” to investigate the matter.He went on to say that other gang evidence related to Mr Hart was intended to show that he was in the MOB and that Warner “was a member of the more juvenile White Hill Crew, but he was able to get access to the MOB which is a more organised criminal establishment”.He said this showed Warner could have access to the gun and was a valid part of the circumstantial evidence led in the Crown’s case.“The picture was used to establish the link between the appellant and that particular MOB gun,” he said. “The evidence was not led for the jury to infer that this man was a member of the MOB.”Ms Christopher also suggested on Monday that trial judge Carlisle Greaves delivered flawed directions to the jury on the issue of identification. She alleged that he wrongly gave the jury the impression there was gun shot residue evidence showing Warner must have fired a gun. And, she complained, his summation was biased in favour of the prosecution.Mr Mahoney rejected all those arguments in his address to the Court of Appeal yesterday, saying the judge “discharged his duty in a balanced and fair manner”.Overall, he said: “The appeal should be dismissed and the conviction affirmed. The evidence was overwhelming and the summation of the trial judge was correct.”The judges hearing the appeal are Sir Robin Auld, Edward Zacca and Sir Austin Ward. This newspaper incorrectly referred to Sir Anthony Evans yesterday, but he is not a member of the current panel.The judges indicated that they will give their decision on the appeal at a later date.