A paramedic just three minutes away from a 14-year-old boy who lay dying in a street was not sent to the scene because of an "end of shift policy".
Lucas Pollard had been riding an electric moped in Bedfordshire in the early hours of June 1 last year when he crashed into a sign post and sustained "very severe injuries" - just a day after he had been given the vehicle.
Lucas' inquest concluded last month. Sean Cummings, assistant coroner for the Bedfordshire and Luton area, explained: "His friend was riding pillion when the bike tilted and then struck a sign post at approximately 20 miles per hour.
"[Lucas] sustained very severe injuries to his chest, liver, spleen and pelvis and suffered a catastrophic internal haemorrhage."
A nearby resident heard the collision and called 999. An ambulance more than 20 minutes away was dispatched, despite a rapid response vehicle (RRV) being only three minutes' drive away.
This was due to an "end of shift policy", the ambulance service said - a policy which limits the calls crews can be dispatched to within the last one hour and last 30 minutes of their shift.
In a report which calls on the East of England Ambulance Service to take action to prevent future deaths, Mr Cummings explained: "The RRV was dispatched by the computer-aided dispatch, but then immediately cancelled by a dispatcher due to the trust’s end of shift policy, seemingly without regard to the actuality of the situation."
Mr Cummings said "there was clear evidence through the [999] call of Lucas’s markedly deteriorating condition", but that "there was no direct dialogue" between the routine dispatcher and the critical care dispatcher.
"Had there been, it is possible, likely even, that the RRV would have been deployed," he said.
While Mr Cummings found that Lucas' injuries were catastrophic and he would not have survived the collision, whatever aid had been provided, he said "that was not known at the time of the call," and "application of the [end of shift] policy as it was, in future situations, may represent a threat to a patient’s life."
He said: "During the course of the investigation, my inquiries revealed matters giving rise to concern.
"In my opinion there is a risk that future deaths could occur unless action is taken."
The chief executive of the ambulance service, Tom Abell, must set out a timetable for action by March 28, or explain why no action is proposed.
A spokesperson for the East of England Ambulance Service said: "We understand the upset and anger that this incident has caused, and our hearts continue to go out to Lucas’ family and friends.
"The end of shift policy was introduced in response to hospital handover delays and the risk of crew members being significantly late off shift.
"This was creating a risk of both unsafe care due to fatigue and late starts for following shifts, which was impacting our ability to respond to patients.
"That policy is currently under review following this tragic incident."
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules here