DNA of teens accused of beach murder was not found on weapon

Two teenagers on trial for murdering a 16-year-old at Irvine beach last year did not have their DNA on the weapon used in the fatal stabbing, a jury has been told.

A 15-year-old boy and Jay Stewart, 18, are accused of killing Kayden Moy on 17 May 2025. Cole Turley, 18, pleaded guilty to the murder before the trial started at the High Court in Glasgow.

Forensic biologist Claire Vallance described items of note seized as part of the investigation into the killing, including a lock back knife which the court had heard was the murder weapon.

Vallance previously told the court only Turley and Moy's DNA was found on the knife.

The trial previously heard that Turley, Stewart and the 15-year-old were part of the Murray Boys gang in East Kilbride, South Lanarkshire.

Moy and his friends were stated to be members of the rival Himshie gang, and an altercation between the groups occurred at the beach.

During cross examination Donald Findlay KC, defending Stewart, asked what conclusion Vallance had made in regards to the weapon.

She replied: "There was no DNA attributed to Jay Stewart on this knife."

Findlay then asked if this was consistent with Stewart never having handled the knife in his life, to which the witness replied yes.

The advocate also asked Vallance if she could say whether deposits of Stewart's DNA found on an extendable baton were deposited at the same time.

Findlay said: "Is the answer 'I don't know'?" and Vallance replied that was correct.

Ian Duguid KC, defending the 15-year-old, put a scenario to the witness where the murder weapon was passed from the waistband of his client to Turley to commit the murder.

The advocate said: "The knife in its entirety had nothing at all which can be identified from the boy?"

Vallance replied: "That's correct."

The trial continues before Judge Lord Scott.