Evidence at the inquest showed that the "war on terror" became the means to implement a secret shoot-to-kill policy, the origins of which laid in measures developed to control public order well before the September 11, 2003 attack in New York.

The government first admitted the existence of Operation Kratos in the week after the July 7 suicide bombings on the London tube and bus system, declaring that "Armed police officers could be given more aggressive shoot-to-kill orders, telling them to fire at the heads of suicide bombers."

The new policy, agreed to by former Prime Minister Tony Blair and former Home Secretary David Blunkett without any public debate, was to sit at the top of a huge body of anti-terror legislation enacted by the government that has empowered the police to act as judge, jury and executioner.

Early on July 22, 2005, the police had identified the communal apartment block in Scotia Road, South London where Menezes was living as the home of Hussain Osman—one of those involved in the failed bomb attacks on the capital the previous day. Intelligence information showed this was also the address of Abdi Samad Omar, who was of "significant interest" in another counter-terrorist inquiry, Operation Ragstone, involving surveillance of young Asian men dressed in khaki and "training" in Cumbria the previous year.

From then on, Scotia Road became the "top priority" for the Metropolitan Police Service (MPS) and leading police officers were drafted in under Commander John McDowall, the Gold Commander in charge of the whole operation. Amongst them were a number of "Operation Kratos" experts.

Yet the police made no move to arrest Osman. Although a surveillance team was posted at the apartment block at 6 a.m., it took almost four hours before a special armed response unit, SO19, was assembled, briefed and dispatched there. Some six people had left the apartment block without being identified and followed before Jean Charles left on his fateful trip to work at 9.30 a.m. Within the space of a few minutes he was described as "worth a look", "unidentified" and "definitely our man."

The first details about Operation Kratos came out at the inquest during McDowall's appearance. It emerged that anticipating footborne suicide bombers was in fact something that had been going on for a number of years... It starts the moment 9/11 [2001] has happened, police in this country, police in many countries, are then beginning to think, ‘It could be us next, but we don't know whether it will be on foot, in the air, marineborne, vehicleborne or whatever'."

Within weeks, a working party was set up to develop a policy headed by Sir David Veness, who had served as assistant commissioner, MPS Specialist Operations since April 1994. He had been a negotiator at the Iranian Embassy siege in 1980 and led the negotiations at the 1984 Libyan Peoples Bureau shooting. He was responsible for security arrangements at major state and ceremonial events and advised in several sieges and aircraft hijackings around the world. In early 2005, Veness was appointed Head of the new Department for Safety and Security at the United Nations after a bombing of the organisation's office in Baghdad on August 19, 2003 but was forced to resign earlier this year after the December 2007 attack in Algiers killed 17 UN workers. An inquiry found that that the bombing came after numerous internal UN warnings about a possible Al Qaeda terrorist attack.

Veness's working party also included Barbara Wilding, now Chief Constable of South Wales and two other officers, Superintendent Steve Swain and Inspector "Zaj", who became the MPS's experts on Operation Kratos. Zaj was one of the night duty firearms advisers on July 21, 2005.

After visiting Israel, Sri Lanka, the US and Chechnya to see how they dealt with suicide bombers, the working party produced the United Kingdom Kratos documents containing three policies to deal with potential suicides. The post of Designated Senior Officer (DSO) was created—the same name given to the senior officer at the Notting Hill Carnival responsible for assessing whether or not a particular type of baton round needed to be used in the event of a riot. This had come about as a result of the public uproar at deaths caused by baton rounds in Northern Ireland.

The first of the new policies, Operation Clydesdale, covered public events such as Trooping the Colour, where intelligence reports suggest a suicide attack is being planned sometime in the future. It say that after the suspect is positively identified and is believed to be carrying a device, the DSO authorises "the delivery of a critical shot, fatal shot in most cases, without warning to the individual, so it's covert, without identifying that you are police officers and so on."

The second, Kratos Person or Kratos People, deals with spontaneous calls from members of the public about suspected bombers and the third, Kratos Vehicle, involved interception of suspected vehicle borne improvised explosive devices. Because of the short timescales, there is usually little time to appoint a DSO in Kratos events and "the model... provides officers and resources with flexibility to deal with the subject on foot, in a vehicle or if absolutely necessary in premises, both for challenge and critical shot options."

It is also clear from the inquest that MI5 and the other intelligence services are "key partners" in Kratos operations and that "military options" are available, but none of these were discussed further.

Soon after the publication of the new policies, specialist firearms officers belonging to Special Operations department 19 (SO19, later renamed CO19) began training at special places in the Thames Estuary and elsewhere and top police chiefs—of Association of Chief Police Officer rank—were trained as DSOs. Commander Cressida Dick, who was the officer in charge of the de Menezes operation, was trained as a DSO during this period along with a number of other senior officers at Scotland Yard.

When the counsel for the de Menezes family, Michael Mansfield, questioned McDowell about the Kratos/Clydesdale policies it became clear that they would inevitably lead to the death of an innocent person. Indeed McDowall indicated that it is likely to happen again.

Q. First of all, is it right that Kratos tends to be a word that is used to cover Kratos and Clydesdale?

A. It has been. It now isn't. It depends on what time you are talking about, I suppose.

Q. Well, July 2005.

A. Yeah, it's certainly been used as a generic term to my knowledge.

Q. Because I'm going to suggest to you that it has resulted in considerable confusion in the minds of all sorts of people because they are not quite sure whether you are talking about Kratos, or Clydesdale.

Mansfield added, "As far as what happened on this day... was quite different to all the very many documents [about Kratos] we have been provided with."

Some of that confusion could be seen in the following evidence.

McDowall said, referring to Kratos/Clydesdale, "It wasn't really one or the other, it was a new situation that I don't think a great deal of thought had been given to, the prospect of failed suicide bombers out and about, it had not come into the thinking, I don't believe."

Chief Superintendent Timothy White, a counter-terrorist commander, agreed that a meeting was called "regarding the need for a specific on-call Kratos DSO for this operation... and after consideration, Commander Cressida Dick was nominated."

According to former Deputy Assistant Commander Brian Paddick, the DSO's role is very specific—purely to make the fundamental Kratos critical shot decision and not get involved in any other aspect of the operation, so that they are "absolutely clear and focused on that decision." He pointed out that "in her evidence-in-chief, [Dick] talks about her role being the interpretation of Mr McDowall's Gold strategy and implementing it, which is quite clearly the role of Silver [a deputy]."

Dick recorded in her log, "I am DSO for Kratos operations for these two premises and the operations to contain and arrest suspects for the attempted bombings yesterday in London who are believed to reside at these addresses... If what appears to be subject leaves premises, we are in Kratos situation."

She insisted, however, that in the case of de Menezes she was asking for "a, what you might call conventional, albeit aware of all the risks, challenge from the firearms officers" that would result in his arrest.

Chief Inspector Esposito, a strategic tactical adviser to the Anti-Terrorist Branch and for Kratos operations, was adamant that the firearms officers were conducting an "orthodox armed intervention" aimed at arresting suspects. "The officers will have challenged the subject and his responses will have resulted in the officers' actions. This was not a Kratos incident," he declared, indicating that a challenge should have been made to de Menezes before opening fire.

The commander of the firearms officers, codenamed Trojan 84, said he had informed his officers that a DSO was in place and that it "would only have been implemented if a suicide terrorism was thought to be—or suicide bomber was thought to be prominent in that day's operation" and "I also said that the team may be required to use unusual tactics today because of the environment they were in and that they should think about this."

Detective Chief Inspector Tony Evans, a MPS internal investigator said he was told that the "surveillance operation had been authorised to follow a Kratos target, but CO19 were unable to intercept him before he alighted the train."

One of the two firearms officers who shot Jean Charles, "C2", said that after hearing the words "Stop him getting on the tube, he must not get on the tube" he believed this was "a relayed instruction from the DSO, and that this suspect was a suicide bomber who had entered the tube in order to blow up a train."

Within minutes Jean Charles was dead.