John Stalker, the honest British cop who exposed “shoot to kill” tactics by the British Army and the RUC in Northern Ireland, has died at age 79.

He was sent over from Britain to probe the deaths of six unarmed Catholics who were gunned down by security forces in cold blood in a one month period in November 1982.

Stalker was on the verge of revealing the full extent of the “shoot to kill” policy when he was abruptly taken off the case by the British government.

It is believed he had an MI5 tape of one of the actual killings, but it never saw the light of day.

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He was deputy police chief in Manchester and when he was first assigned to investigate the “Shoot To Kill” in 1984 there was widespread suspicion that he would be part of a cover-up but Stalker proved the doubters wrong earning the deep respect of Irish nationalists in the process.

A trumped up charge that he had associated with an English mobster was the reason given for his dismissal. He was later cleared of any wrongdoing.

In one of the incidents the Stalker inquiry in Stalker’s own words “discovered that the three victims of the shooting had been under surveillance for many hours by the police who planned to intercept them at a place different from where the killings occurred. No serious attempt to attract the attention of the driver was made, and no policeman was struck by the car. 110 bullets were fired at the car.

“Immediately after the incident the police officers drove from the scene with their weapons and returned to their base for a debriefing by senior Special Branch Officers. Officers from the Criminal Investigation Department (CID) were denied access for many days to the police officers involved and to their car, clothes and weapons for forensic examination. On the night of the killings, CID officers were given incorrect information about where the shootings began and part of the forensic examination was conducted in the wrong place. Many cartridge cases of rounds fired were never found.

“We believed... that at least one officer had been in an entirely different position from that which he had claimed to be in when some fatal shots were fired. I also established that the police pursuit took place in a different manner from that described. But most damning of all, almost 21 months after the shooting we found fragments of the bullet that undoubtedly killed the driver still embedded in the car. That crucial evidence had lain undiscovered by the RUC and Forensic Science service... My conclusion in relation to the missing cartridge cases was that as many as twenty were deliberately removed from the scene. I could only presume that this was in order to mislead the forensic scientists and to hide the true nature and extent of the shooting.

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"I had to regard the investigation of the matter as slipshod and in some aspects woefully inadequate. I was left with two alternative conclusions, either that some RUC detectives were amateur and inefficient at even the most basic of murder investigation routines; or that they had been deliberately inept.”

Concerning the three incidents as a whole, Stalker wrote: “Even though six deaths had occurred over a five-week period... and involved in each case officers from the same specialist squad, no co-ordinated investigation had ever been attempted. It seemed that the investigating officers had never spoken to each other. Worse still, despite the obvious political and public implications, no senior officer had seen fit to draw the reports together.

“We had expected a particularly high level of enquiry in view of the nature of the deaths, but this was shamefully absent. The files were little more than a collection of statements, apparently prepared for a coroner's enquiry. They bore no resemblance to my idea of a murder prosecution file. Even on the most cursory of readings I could see clearly why the prosecutions had failed.”

After he was dismissed the inquiry was carried on by his deputy John Sampson but the Stalker/Sampson report was never made public. In his book Stalker revealed many of the key findings.

Former Manchester Central MP Tony Lloyd, who raised Mr Stalker's case in Parliament in the 1980s, said he was "a man of great integrity who was treated unjustly.”

A four-hour film/documentary was made in 1990 recreating the killings.