The Court of Appeal was urged to overturn a murder conviction on the basis that fresh evidence had arisen.

Jerome Lynch QC, lawyer for Khyri Smith-Williams, told the court last week that two affidavits, one signed and one not, could raise doubts on the evidence of a key prosecution witness. Carrington Mahoney, for the Crown, argued the evidence was not “fresh” and was of no consequence.

He told the court: “It adds nothing to the essence of the case.”

Smith-Williams was sentenced to serve at least 35 years in prison last October after he was found guilty of the murder of Colford Ferguson by a majority verdict. Mr Ferguson, a 29-year-old father of one, was shot dead in February 2011 as he worked on a house near the junction of Mangrove Bay Road and East Shore Road in Somerset.

Prosecution witness Troy Harris told the court that Smith-Williams, a member of a West End gang, confessed his involvement in the killing to him and admitted that he had driven the getaway motorbike.

He said that Smith-Williams told him Rasheed Muhammad had pulled the trigger and that the wrong man had been killed.

Mr Lynch told the Court of Appeal he had received an unsigned affidavit from Mr Muhammad in which he denies that he was involved in the shooting.

He told the court Mr Muhammad had not given evidence in the trial out of fear for his own safety and that of his family, in which case the court could hear arguments to allow the statement as evidence.

Mr Lynch said: “The issue ultimately is whether or not this is someone who is deliberately avoiding giving evidence because he doesn’t want to or if he is genuinely concerned for his safety, genuinely concerned for his family.”

He said there was also an affidavit from a witness who had seen the suspected gunman before the shooting.

Mr Lynch said his evidence had been admitted as part of “agreed facts”, but in his full sworn statement the witness said he had known the man prosecutors claimed was the gunman.

He said: “That would be an important feature against that background to say that he did not identify the suspect as being the person who had been responsible.”

Mr Mahoney, however, said the witness’s evidence added nothing to the facts of the case and the witness could not be called during the trial because he left the country.

On the issue of Mr Muhammad’s unsigned affidavit, he said the defence could have called Mr Muhammad during the trial as he was in the jurisdiction, and actually in the courtroom, during the trial.

“He was available,” Mr Mahoney said. “This trial ended in October and within a week the grounds of appeal were filed indicating that the defence intended to provide fresh evidence.

“This particular part of the evidence has a multitude of problems. The affidavit is unsigned, his police interview was in their possession and he was in the jurisdiction.”

Mr Mahoney also questioned the claim that Mr Muhammad was afraid to testify.

He said: “He has claimed that he was a member of [a gang]. Colford Ferguson wasn’t a member of any gang, so when he said he was fearful, fearful of who?”

Mr Lynch also raised concerns about the conduct of Puisne Judge Carlisle Greaves, specifically his exchanges with Mr Harris while he was on the stand.

He argued that Mr Justice Greaves took a “jovial approach” to the witness who claimed in evidence that he “shared women” with Smith-Williams.

The QC said the exchange was “inappropriate and highly prejudicial” and caused his client great concern that he had not been treated fairly. Mr Mahoney argued that the dialogue between the judge and the witness “added up to nothing”.

He said: “In a normal cut and thrust of a criminal trial these are the type of things I would expect, particularly when people have different ways of expressing themselves and people have different approaches to interpreting and understanding these persons.”

Mr Mahoney added Smith-Williams’s rebuttal evidence on the subject of Mr Harris’s claims also caused laughter in the court, but no complaints had been made about that exchange.

The hearing concluded and a judgment will be given at a later date.

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