Michael Mansfield QC, counsel for the Lawrence family, told the public inquiry into Stephen's death that this was the inference to be drawn from the failure by detectives to act on early tip-offs about the identity of the killers.
The inquiry was abruptly adjourned yesterday to permit the highest-ranking officers in the case to consult their lawyers, after Mr Mansfield indicated that he planned to raise the possibility of a conspiracy among them to subvert the murder investigation. It will not now sit again until Wednesday.
The allegations of corruption came during questioning of Detective Sergeant Christopher Crowley, who discredited vital identification evidence, leading to the collapse of a private prosecution brought by Stephen's parents, Neville and Doreen.
They revolve around Clifford Norris, father of David Norris, one of five youths charged with killing Stephen. The inquiry has heard that Norris was a dangerous criminal who was known to buy off witnesses and jurors and, according to rumour, police officers.
David Norris was one name repeatedly mentioned by police informants soon after Stephen was stabbed to death in Eltham, south London, by a white gang in 1993. Others included Neil and Jamie Acourt, whose three uncles, from a family called Stewart, were criminal associates of Clifford Norris. Despite the deluge of tips received by detectives, no arrests were made for two weeks.
Mr Mansfield said he was not suggesting that DS Crowley himself had connections to the Norris family. "What we do infer from the circumstances of this case, given the way in which the intelligence was not used in the early days, is that an officer, somewhere, must have known the Norrises," he said.
"The Norris family is capable of corruption, and that is beyond dispute. There must have been a connection with a police officer. It is not known which, since very few files, including this officer's, have been made available.
"The fact is that this was one of the best-known names, and it was not researched in the early days. And from the Norris family to the Stewarts to the Acourts, there would have been a very strong inclination to protect the Acourts."
DS Crowley, who escorted the main prosecution witness to an identification parade but was not on the murder inquiry team, said that he had "no knowledge" of corrupt links. "Do you know a DS Coles on the Flying Squad?" asked Mr Mansfield. "I've never heard of him," he replied.
He said he knew very few of the detectives who investigated the murder - in contrast, Mr Mansfield pointed out, to his assertion at the committal proceedings that "I know most of the officers, possibly, in the whole inquiry team."
Mr Mansfield said that Clifford Norris, who is now serving eight years for drugs and firearms offences, was at one time "wanted for a murder, but the murder was dropped because witnesses had been intimidated".Reuse content