Chief police officers kept a controversial shoot-to-kill policy against suicide bombers secret from the public because they feared it would be "watered down".
Barbara Wilding, one of the architects of the strategy known as Operation Kratos, has revealed that members of the Association of Chief Police Officers (Acpo) advised against a national debate when the new guidelines were drawn up three years ago, because people did not understand how serious the threat was from suicide bombers.
Ms Wilding, the Chief Constable of South Wales Police, also said the team's work, which recommended that suspected terrorists should be shot in the head without warning, was "ridiculed" by top-ranking officers.
"I was told it [suicide bombings] would not happen here and that the public would not accept it [the policy]," said Ms Wilding in an interview with Police Review magazine.
There was criticism of the Metropolitan Police when it emerged that officers had been acting under Operation Kratos when they gunned down Jean Charles de Menezes at Stockwell Tube station last year.
MPs were furious that the Home Office was aware of the guidelines but that they were not publicised or discussed in Parliament before being introduced.
The Crown Prosecution Service (CPS) is considering whether to bring charges against more than 10 officers involved in the killing of the 27-year-old Brazilian electrician, who was shot eight times.
Officers have always used a shoot-to-stop policy, which allows them to fire into the upper body to shut down the central nervous system quickly.
However, senior officers ordered a switch in approach after the escalation in the terror threat to Britain from al-Qa'ida.
Ms Wilding and the Acpo group set up to form a policy on tackling suicide bombers visited countries with experience of such attacks, including Israel.
Their research revealed that repeated shots to the head were the only way of stopping someone intent on detonating a bomb.
The controversial tactic means that officers do not need to shout a warning and police are not required to identify themselves if they judge the intelligence is strong enough that the suspect is intent on mass murder.
Since the 7 July attacks, the Met has identified 250 incidents during which police thought they might have been dealing with a suicide bomber.
There is widespread concern, however, about guidelines surrounding the use of Operation Kratos, even among senior officers. Acpo is understood to be carrying out a review in the wake of the Stockwell shooting.
Defending the policy, Ms Wilding accused senior officers of "jump[ing] on the bandwagon" after the 7 July attacks by reassuring the public that police had tactics to combat bombers.
"Suicide terrorism officers have to make the decision if they can stop a suspect," she said.
"If [the suspect] is behaving strangely the [officers] have to launch a pre-emptive strike."Reuse content