Saunders’s life ended when nine officers from the specialist CO19 gun squad, part of a 24-hour Armed Response Vehicle squad, opened fire from a distance and five bullets, from three different guns, tore apart his body. They then fired stun grenades into the flat and stormed in to find him dead. The pathologist at the inquest that followed said, “The multiple gunshot wounds present are associated with severe internal damage to the brain, the heart, the liver and the main vein of the lower body.”

The police claim Saunders was killed according to “shoot to stop” guidelines, under which marksmen are supposed to incapacitate their target by firing at the torso.

However, the nature of the personnel involved in the killing of Saunders and the extreme force they employed has more in common with the Operation Kratos “shoot-to-kill” policy, secretively adopted six months following the September 11, 2001, attacks.

Operation Kratos only became public knowledge after the July 22, 2005, shooting of Brazilian Jean Charles de Menezes by SO19 (now called CO19) firearms officers. At the time, government ministers and senior police officers claimed the new strategy had been adopted to deal with suicide bombers and that it would only be used under exceptional circumstances. Within months of making these assurances, the Independent revealed that far from reining in the “shoot to kill” strategy following de Menezes’s death, it was widened to include other offences such as kidnapping, stalking and domestic violence.

Mark Saunders is now the eighth person to have been shot dead by police since de Menezes’s killing.

Reports are mixed as to the extent to which Saunders posed an immediate danger, but it appears the decision was taken to end negotiations, which seemed to be going well, and embark on a course of action that meant he would never leave the house alive.

According to neighbour Penelope Russell, there was nothing unusual when she saw Saunders and his wife on the day before the shooting. “They told me they were going for a walk to St. James’s Park as it was a lovely day,” she recalled. “They looked perfectly normal.”

On the morning of the shooting, Saunders e-mailed his mother at 7:30 a.m., but he gave no indications of what was to follow. The couple left for work at top legal firm QEB, where they earned £200,000 a year each as barristers specialising in divorce and custody disputes and were regarded as a “golden couple.”

Around lunchtime, Saunders returned home. At about 5 p.m., shotgun fire was heard coming from his apartment. Neighbour Jane Winkworth explained, “Mark came in and he was quite quiet. I was in the garden doing some shoe designs.

“About half an hour later I heard gunshots being fired into the garden. I assumed it was an airgun and he was shooting pigeons, but after he fired two more I realised it was a proper gun.

“When I screamed at him to stop, he didn’t say anything. It was as though he wasn’t listening.

“I ran into the flat, terrified, and called the police. All he kept saying to the police was ‘I can’t hear you.’

“He was mumbling stuff like a drunk person would, but he wasn’t shouting or being aggressive apart from when he was shooting. The shots were very loud. They were absolutely terrifying.”

Saunders later threw a piece of card from a window on which he had written, “I love my wife dearly. xxx”

According to Penelope Russell, the police said the siege “could go on for a very long time, as he was in his own house and there was food and drink there that could last for days.” But suddenly, the atmosphere changed and she was bundled out of her home. It appears the change took place after the intervention of Scotland Yard’s “gold command” and the permission granted by Commander Ali Dizaei to use firearms. It was the same gold command structure under Cressida Dick that was responsible for the de Menezes shooting.

At this point, the police story becomes contradictory. According to one police source, Saunders “was firing directly at people and police officers and into houses which had not been evacuated. He was a direct threat. There were attempts to engage him by negotiators but these were not successful. This man was out of control and we could not predict what he would have done next.”

In contrast, neighbour Lesley Hummel said, “I remember thinking that Mark was very calm. I saw how he was reloading his shotgun. He never pointed the gun out of the window; he stood in the darkness of the room and calmly raised the shotgun to his face to take aim. He wasn’t shaking, he wasn’t shouting or saying anything.”

More recently, the Daily Telegraph reported that “police negotiators who were trying to persuade Mr. Saunders to surrender felt they were close to a breakthrough shortly before the siege on May 6 came to its bloody end.”

As with the de Menezes case, the authorities rushed to cover up the facts surrounding Saunders’s death and obscure them with deliberate misinformation. The media played its part with lurid tales of a drunken, depressed “rich kid” who got what he deserved.

The Times reported that Elizabeth “had decided, because of her husband’s increasingly drunken and erratic behaviour, that she could no longer love him or live with him” and following an argument, had “run from the house in tears about 4 p.m. [setting] off the extraordinary series of events that ended with police marksmen shooting Mr. Saunders dead at 9:30 p.m.”

One report quoted a detective who claimed the argument was about “his alcoholism and his infertility.” Other stories circulated saying that Saunders had a history of depression and, because he was in the depths of despair, had opted for “suicide by cop” or that he was an Iraq veteran who had gone on the rampage.

Tony Parsons, writing in the Daily Mirror, positively revelled in Saunders’s death. In a comment piece, “Shooting the Rich,” he said, “I can’t believe I’m the only one who felt enormously relieved when this trigger-happy, half-cut nutter was shot dead.”

The Saunders family responded in a calm and dignified manner as they struggled to understand the reasons for his actions. After the inquest, they released a statement saying, “Everyone who knew and loved Mark appreciated his warmth, generosity and sheer energy for life. He was a very talented and sociable person whose enthusiasm and charm touched so many people. We will always remember him as our caring, considerate and loving son and brother.”

Elizabeth said that she and her husband of 18 months had “a strong union” and were “deeply committed to each other.”

Mark’s father Rodney Saunders questioned why the police had been unable to end the siege peacefully, adding, “Put it this way, he didn’t endanger anyone at all to my knowledge and we can only surmise what might have happened before the whole thing started.

“I just don’t know. You would imagine that it will come out in the fullness of time. We will want answers as to why police shot him.”

His mother Rosemary said she had not been aware of her son having any marital problems and that his wife was at work when the siege began and had been stopped by a police cordon as she tried to get back into her flat.

“Liz was his life but his work also meant everything to him. Everything he touched he was successful in. He had a stressful job but never spoke about any undue pressures or stresses.

“Mark did have drinking issues, but we are at a loss as to explain what happened. All we know is we’ve lost our son. What went wrong I just don’t know. I don’t know if we’ll ever know.”

Rosemary Saunders’s fears are well justified. The Independent Police Complaints Commission has started an investigation into the shooting, but the de Menezes police killing provided some fundamental political lessons. The Crown Prosecution Service (CPS) rejected any criminal proceedings against any of the officers directly involved in the shooting and those who commanded them on the spurious basis that there was “insufficient evidence to provide a realistic prospect of conviction.” To add insult to injury, the CPS prosecuted the Metropolitan Police under the Health and Safety at Work Act 1974 for “failing to provide for the health, safety and welfare” of Jean Charles.