Former Metropolitan Police deputy assistant commissioner; Born September 25, 1920; Died October 17, 2008.

John Morrison, who has died aged 88, was a former seaman who went on to become deputy assistant commisisoner with the Metropolitan Police and became involved in some of the most celebrated murder cases of the 1970s.

Morrison, of New Tolsta, Lewis, died in the Bethesda Care Home and Hospice in Stornoway. The seventh of a family of 10, he began work as a crewman on the family fishing boat, The Good Hope, but in 1938 he joined the Royal Navy Reserve and saw various parts the world, including convoy duty to Russia, but survived the many hazards including icebergs, submarines and bombers working from occupied Norway.

In 1944 he was with an armada of other ships off Normandy for the D-Day landings. Demobilised in September 1945, he recalled that it had been a worrying time for the family, with five sons at sea.

A year later he was accepted by the Metropolitan Police - at 5ft 10ins he had been too short for the Glasgow police force. Morrison took up plain-clothes duties and after three years' service was transferred to Scotland Yard and then to the fraud squad.

He progressed through the ranks and spent time with the murder squad and then became a detective inspector and was transferred to the west end central police station. In 1968 he was promoted and posted as detective superintendent to Brixton L division. A year later he returned to the Yard as chief superintendent and staff officer.

He was eventually promoted to commander and posted to C9, which was responsible for the regional crime squads within the Met area. In 1973 he flew out to Bermuda to investigate the murder of the governor, Sir Richard Sharples. Sir Richard was shot dead by assassins linked to the militant Black Beret Cadre, a small Bermudian Black Power group. The killers were caught and eventually hanged.

Morrison was also involved in the Black Panther case in 1974 when three sub-postmasters were murdered in Yorkshire, Lancashire and in the West Midlands. In each case the intruder, masked and dressed in black clothing, killed to effect his escape when disturbed by the occupants. The culprit was later identified as Donald Neilson, who had also abducted and killed the heiress Lesley Whittle.

By the time of the trial, Morrison had been elevated to deputy assistant commissioner. In 1976 he was awarded the Queen's Police Medal and the following year was made an OBE.

Prior to retiring to his native isle, where he was known locally as Commander Morrison, he became security adviser to the newly-formed British National Oil Corporation. The head office was in London, in Stornoway House, next to St James's Palace, although he was based in Glasgow. Stornoway House was so named because at one time it was the London home of Sir James Matheson, who in the early part of the century owned Lewis and Harris. During the Second World War, it was Lord Beaverbrook's headquarters.

In his retirement, he published a roll of honour for the Tolsta area, and also a book entitled Lewis Seamen - 1939-1945. Morrison is survived by Nandag, his wife for 57 years, who is also a resident in the Bethesda Care Home, and Joan, Ian, Anne and Donald. His wife's brother, Alex, became chief constable of Grampian Police.

Bill Lucas