Gerald Mannering was the son of a gentleman but was no gentleman himself. Indeed Gerald was the perpetrator of the murder of the only policeman to be killed whilst on active duty in Derby.

Mannering had travelled to Derby after arguing with his father and embarked upon a drinking spree. He was spotted by the police driving a pony and trap whilst drunk and was arrested in the yard of the Traveller's Rest public house on Ashbourne Road.

He was taken to the police lock-up that stands where the Derby Fish Market is now situated. Unbeknown to the police who had not searched him he was carrying a loaded pistol and whilst in the Charge Room he drew the gun and began to fire wildly. He wounded one Inspector and shot dead PC Moss.

Although found guilty Mannering escaped the death sentence when it was discovered that the jury had been split 50-50 over whether it had been murder or manslaughter, and had drawn lots to decide which jury member would have the casting vote.

Although Mannering had escaped with his life PC Moss hadn't. Maybe it is because of this reason that the soul of PC Moss has never been able to rest. Many people who have worked at the fish-market have seen a policeman in a "Victorian-style uniform" watching them and have heard phantom footsteps patrolling the yard.

Perhaps PC Moss will forever patrol the old Lock-Up until his spirit can find peace.