n December 1997, Sir Paul Condon, then commissioner of the Metropolitan Police, addressed a House of Commons committee on the scale of corruption in his force. "If you want a percentage figure on it," Condon said, "I would hope and believe it is contained somewhere between 0.5 per cent and 1 per cent. There is a spurious precision to that, but I would say somewhere between 100 officers and 250 officers would be the range in which we are operating."
At roughly the same time, an internal report on police corruption across the country was leaked to the press and it put the matter in even starker terms, saying that the problem was so "pervasive", it could have reached what was called Level Two, defined as "the situation which occurs in some third world countries".
Michael Gillard and Laurie Flynn, two former Guardian journalists who seem to have ploughed this nasty furrow as deeply as it is wise or safe to do, begin by pointing out that, if there really were 250 corrupt police officers in London in 1997, then 200 are probably still unaccounted for in 2004. A few, it appears, are on an internal blacklist identifying them as untrustworthy, while some will have retired. The rest, by implication, are out there in the city to this day, mixing their crime-fighting with crime-committing, and no doubt suborning colleagues as they go.
Nor are they necessarily small fry. One gangster is quoted here as protesting, when challenged about his relations with a lowly detective, that he never dealt with anyone below the rank of commander - that's just four promotions away from the commissioner's chair. The implications are alarming. Stories told in these pages involve murderers going unprosecuted, armed robbers being wrongly acquitted, innocent people being framed, drugs hauls going missing and six-figure sums disappearing while apparently in police hands. Clearly, besides effective independent official scrutiny, there is a need for a well-documented, well-argued and authoritative book about the problem as it has developed in recent years. Sadly, despite the wealth of information it contains, this is not that book.
Part of the problem is the style. Perhaps because they have spent too long in the company of detectives and criminals, the authors adopt a macho argot that devalues their research. People are "nicked" and "grassed on", money is "divvied up" and suspects "cough". Worse, a detective having a nervous breakdown is described as "imploding at a rate of knots", while another who kills himself has chosen to "wrap his guts around a shotgun".
A bigger difficulty lies in the tangled character of the narration, which, spread over 500 pages, represents a real impediment to understanding. This book is such a dense maze of names, dates and crimes that it is all but impossible to gain a perspective on the problem; it should have been edited with more care. Moreover, one accusation levelled by the authors actually ends up defeating their purpose. The world of police corruption is rather like the world of spies: it resembles a wilderness of mirrors in which everyone is playing a double game. If one officer accuses another of taking bribes, it seems that the first thing that will happen to him is that he in turn will be accused. (Gillard and Flynn say this happened even to them.) The police investigators themselves are often under suspicion and the bad smell of one accusation, even if unproved, never leaves them.
Several times during the story you find yourself wondering: how can anyone ever tell who is honest and who is not? How is it possible to choose, as the authors have at times done, to believe one witness in a particular case, but doubt another? You feel an unexpected pang of sympathy for Paul Condon and his successor, Sir John Stevens, who have had to deal with this mess.
Difficult as it is to see the wood for the trees in this forest of crime and deception, we do get the odd glimpse. Scotland Yard's attempts to police the problem appear to have been ill-conceived, its personnel all too easily tainted by what they encountered. Equally, the strategy of paying practising criminals to inform on police officers seems to have been self-defeating.
External scrutiny of the most vigorous kind is needed - a point that was also made by the Macpherson report into the Stephen Lawrence case in 1999, and which is supposed to have been addressed by the creation of the Independent Police Complaints Commission this year.
Gillard and Flynn do not like the look of the IPCC, chiefly because they don't like the director of investigations, Roy Clark, a retired police officer who was for years in charge of Scotland Yard's anti-corruption drive, and so by their standards is not independent at all. Let us hope, in the public interest, that in due course someone writes a book telling us whether the IPCC has proved effective; and let's hope it is a good book.
Brian Cathcart is the author of The Case of Stephen Lawrence (Penguin)