A former police colleague of Willie Greenshields would like to get in touch to discuss old times.

A former police colleague of Willie Greenshields would like to get in touch to discuss old times.

However, this will be no fond reunion, over a pint: Willie would not be surprised if the detective set about him with his police-issue truncheon.

The man is said to be rattled by a passage in Willie's first book of Strathclyde Police reminiscences, Greenshields: A Glasgow Cop.

Willie liked and admired many of the officers he came across, but he does not pull his punches when it comes to describing those who he saw as lazy, drunk or incompetent.

Taggart, it isn't.

"I have had a good reaction to the book generally, apart from this one detective in particular," says Willie.

"He is livid, but I don't know why because he comes out of it quite well. He was always a bit erratic. Maybe it is seeing his name - or almost his name - in print."

Undaunted by any adverse reactions, Willie is now working on a second book of memories.

The first one ("based on actual events") teems with anecdotes: how he once arrested one of his own second cousins for murder, and how he once took part in a Serious Crimes Squad raid that uncovered guns and ammunition destined for an Ulster Loyalist group.

After one drugs bust, he recalls, a man who had been detained said he could return guns that had been stolen from a well-known city store if he could work out a deal with the police and the fiscal.

Willie asked him if he was in a position to return the guns. "Aye," came the reply. "I'm Arthur Thompson's armourer."

The man later left an automatic handgun concealed in a pram in a dingy close in Garngad, followed by a larger haul in a car parked at a pub.

Shettleston-born Willie spent much of his career with E division, which covers the East End, and rose to the rank of detective, graduating to the Drugs Squad.

He dealt with everything from gangland killings to rapes, assaults and thefts.

Once, he and a handful of colleagues arrived at an East End flat on a drugs bust. One of the men present was a particularly sadistic gangster.

One officer asked the thug what he was into. In a stage whisper, Willie muttered "little boys". The gangster, enraged, wanted to take him "round the back".

He calmed down - but filed a complaint against Willie.

"Bloody cheek," was Willie's indignant reaction. "He has shot, stabbed, tortured and robbed - and because I offended him, he thought I should be punished."

One of the many cases he investigated was a brutal rape in the East End.

A terrified young mum had been sexually assaulted in front of her child and suffered serious knife wounds to her hands.

She told police her assailant had a terrible smell on him, and also gave them a nickname that eventually led Willie and other detectives to a rundown flat.

The man's mother said she hadn't seen him for weeks. But they did not believe her, and entered the house.

"The bedroom stank and I understood exactly what the girl had meant," he says.

He found the man curled up in a ball beneath the single bed. "My self-control had suddenly gone and I booted him as hard as I have ever kicked anything in my life."

Years later, Willie heard that the man had served five years for that rape - but had committed another rape on his release and had been jailed for life.

The forthcoming book makes a sensational allegation about another former cop.

John', a middle-man in cocaine deals, had done a deal that saw him escape with a warning letter in exchange for the promise of information about drug-dealing.

No-one knew just how good the information would turn out to be.

"He told me about a robbery at a restaurant," says Willie. "The manager had been handcuffed to a radiator and pistol-whipped until he agreed to open the safe, which contained thousands of pounds, which the thieves escaped with.

"Then John told me the name of the man who had possession of the firearm. It was a serving police officer from another force - and the gun had been stolen from a senior colleague.

"He also told me the officer had bought ecstasy tablets with his share of the proceeds - and had transferred them to Northern Ireland hidden in the bodywork of a car."

Willie reported the matter to a senior CID officer. He never discovered what became of the rogue cop - but trusts the authorities dealt with him.

John', incidentally, also belonged to a Loyalist paramilitary organisation, and provided Willie with a copy of one of their training videos.

Special Branch took on this case, and Willie's contact with John' ceased. "I was glad to be out of it. It's one thing to catch drug dealers, rapists, robbers and even the occasional murderer, but terrorist organisations were out of my league."

The ex-cop is frank about why he has written of his experiences. "I had so much knowledge inside my head and I didn't want to lose it. There are 27 or 28 years in the book and in the new one.

"Sometimes I've given people names that aren't a million miles from their real one. They'll know who they are. The book itself is accurate. It had to be written."

As before, there is the usual smattering of Glasgow cops - the good, the bad and the ugly - in all their glory.

One cop came down with sunstroke after allowing the sun to blaze down on his unprotected bald head during a stake-out.

"Members of the public have loved the book, because it shows the true side of policing," says Willie.

"It's not as if the cops are all good guys. They're not. They tell lies, they swear, they sleep round - they do all that."

Taggart, it most definitely ain't.

• Greenshields: Still A Glasgow Cop will be published before Christmas.