Dressed in a smart blue suit and tie, clean-shaven and with neatly cropped fair hair, Michael Ross looked every inch the respectable off-duty soldier as he sat for week after week in Court No 3 at the High Court in Glasgow.

A sniper with the Black Watch, the 29-year-old sergeant was praised in dispatches in 2005 for his bravery after his unit was hit by suicide bombers in North Babil, part of Iraq’s “triangle of death”, killing three soldiers and injuring seven.

Married with two young daughters, he was portrayed by his defence QC as a gentle family man who had wept when a black soldier under his command was killed. His captain testified in court that he was one of the finest soldiers he had ever served with.

But despite the glowing character references, Ross was not what he seemed. Two months before his 16th birthday he strode nonchalantly into an Indian restaurant and, from a range of two feet, shot a 26-year-old stranger in the head for the simple reason that he objected to the colour of his skin.

For a 15-year-old schoolboy to commit such a murder would be unthinkable anywhere, but nowhere more so than in Orkney.

Shortly after 7.15pm on Thursday, June 2, 1994, the Mumutaz Indian restaurant in Bridge Street, Kirkwall, was beginning to fill up with customers when the door swung open and a blast of cool air filled the room. Shamsuddin Mahmood, the restaurant’s Bangladeshi manager, was serving a family of six when a man in a balaclava and hooded top walked up to him, pointed a gun at his face and pulled the trigger.

As Ross ran down an alleyway and ripped off his clothes, the 26-year-old man was convulsing on the carpet. What had been the left side of his face had been sprayed across a 12-year-old girl who had been sitting having dinner with her sister, parents and two other relatives.

In the instant that it took Ross to kill Mr Mahmood, Orkney’s reputation as a crime-free idyll was shattered. The Rev Ron Ferguson, leading prayers at St Magnus Cathedral in Kirkwall, said: “People are shocked and stunned by this. It’s the sort of thing you expect to happen in London, not in Orkney.” Before that day there was nothing to suggest that bloody murder was about to come to Kirkwall’s narrow streets and wynds.The Orcadiannewspaper that day contained the usual stories about petty theft and vandalism, but nothing even close to violent crime. The islands’ detectives were busy investigating the theft of a bike from outside a Kirkwall shop (it was later recovered, though damaged), and the smashing of a window at another store. As tourists poured into the islands to enjoy the long summer evenings (sunrise that Thursday was at 3.10am, sunset 9.11pm), a man named Catfish Keith from the USA was performing his Country Delta Blues at a hotel in Evie; Ace Ventura: Pet Detective, starring Jim Carrey, was showing at the Phoenix Cinema in Kirkwall; and the Matchmakers Disco was gearing up for another late night. Posters in the town advertised a Shiniest Bottom contest (for boats).

Mr Mahmood’s killing, the first on the islands for 25 years, could not have been more unexpected; as the local police chief later admitted, his officers had not even drawn up contingency plans for a murder. Such was the concern after the killing that one girl kept her horse in the house because she feared that it might be attacked.

The second youngest of seven brothers and four sisters, Mr Mahmood, known to friends as Shamol, grew up in Dhaka, the capital of Bangladesh, where he studied economics at university. After coming to Britain, he first worked at the Mumutaz in the summer of 1992, moving to Kirkwall from the home of one of his older brothers, Abul Shafuddin, now 63, a barrister who lived in Southampton.

Intelligent and hard-working, he was well-liked by colleagues at the Mumutaz and returned in April 1994, this time taking a job as the restaurant’s manager. Slightly tubby and with large glasses and an eye-catching hair-style, he was described by those who knew him in Orkney as happy-go-lucky and full of fun. Several had nicknamed him “Handsome”.

Mr Shafuddin said of his baby brother: “As a family, we cannot believe he could have had any enemies or that anyone could have a motive to kill him.”

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