Six Red Caps killed by a mob in Iraq in 2003 should have been better equipped, but their deaths could not have been avoided, a coroner has said.
The inquest was told the men had no way of calling for help
Coroner Nicholas Gardiner said he would write to the defence secretary in an attempt to prevent further fatalities.
But the military policemen's relatives said Scotland Yard should investigate and that officers responsible for mistakes should be court-martialled.
A narrative verdict of unlawful killing was recorded over the deaths.
The coroner said the men should not have been given antiquated radios and inadequate ammunition, and said he would write to Defence Secretary John Reid about army equipment and procedures.
The families are calling for a public inquiry and believe the Army failed in its duty of care to the men.
The soldiers had 50 rounds rather than the standard 150 rounds and had left base without an iridium satellite phone.
But the coroner said having and using better communications would not have saved the men on that day.
"Neither the air reaction force nor the quick reaction force [despatched after reports of fire fights from nearby paras] could have effected a rescue for that time even if they had known that the RMPs were at the police station," he said.
He said he was clear commanding officer Colonel Beckett had ordered all patrols to carry the phones, but could not ensure all 1,500 troops did so and there was a need for one of the links in the chain to be proactive and comply.
"It is not for me to identify the particular link, but it is a matter which I shall cover in the letter," he said.
The inquest, in Oxford's Old Assizes, heard previously Lieutenant Richard Phillips, the officer in charge of the six RMPs, had not known that the men were meant to carry the phones.
SIX DEATHS IN IRAQ
Cpl Simon Miller
21, from Tyne and Wear
Sgt Simon Hamilton-Jewell
41, of Chessington, Surrey
Cpl Russell Aston
30, of Swadlincote, Derbyshire
Cpl Paul Long
24, from Tyne and Wear
L/Cpl Benjamin McGowan Hyde
23, of Northallerton, North Yorkshire
L/Cpl Tom Keys
20, of Bala, North Wales
The coroner said Sergeant Simon Hamilton-Jewell appeared not to know that paratrooper units were in the town and might have come to their rescue.
And he criticised the assessment of the area where the men died as "benign but fragile".
The six Red Caps killed were Sgt Simon Hamilton-Jewell, 41, from Chessington, Surrey; Cpl Russell Aston, 30, from Swadlincote, Derbyshire; Cpl Paul Long, 24, of Tyne and Wear; L/Cpl Benjamin McGowan Hyde, 23, from Northallerton, North Yorkshire; L/Cpl Tom Keys, 20, from Bala, North Wales; and Cpl Simon Miller, 21, from Tyne and Wear.
Pat Long, whose son Corporal Paul Long died, said: "The army was at fault and could have looked after the men better.
"I hate to think of any other family having to go through what we've had to go through."
Reg Keys, who lost his son Tom, said their deaths had been caused by negligence.
"Yes, we accept the risk a soldier takes.
"For goodness' sake, give them the equipment to do their job.
"To withhold that equipment and send them into a hostile town boils down to a lack of duty of care and a cavalier attitude to the safety of these men."
MoD spokesman Colonel Peter Davies said his "heartfelt sympathies" were with the families and friends of the men.
He added: "We will be considering carefully all of the implications of the inquest's findings, and the coroner's recommendations to the secretary of state as a matter of the utmost importance."
He said a new radio system had already improved communications.
Responsibility for catching the killers lay with the Iraqis, he said, but the MoD were offering help.
The inquest heard graphic evidence about how the men, from Goojerat Barracks in Essex, died in an attack on a police station in Majar al-Kabir.
The inquest heard that the first the men's commanding officer knew of their whereabouts was when he was told their bodies had been found.
It also heard that on the day of the killings the mob had been hunting down coalition forces.
After being repelled by paratroopers earlier in the day, the crowd then found the six men in the town's police station.