Greater Manchester Police are to face charges over the death of Pc Ian Terry who was shot dead by a colleague in a bungled training exercise.
The force said it was to be prosecuted by the Health and Safety Executive over alleged breaches that led to the death of the officer and father-of-two in June 2008. Two GMP officers are also being prosecuted by the HSE.
The development comes after the Crown Prosecution Service announced on Tuesday that there was still insufficient evidence to bring criminal charges against the force in relation to Pc Terry's death.
GMP Assistant Chief Constable Garry Shewan said: "The Health and Safety Executive has today announced that it is to prosecute Greater Manchester Police and two of our officers for breaching section 2 and section 7 of the Health and Safety Act.
"It has been nearly four years since Ian Terry tragically died, four years that Ian's family and colleagues have had to wait for this protracted decision to be made."
An inquest held at Manchester Coroner's Court in March 2010 found that Pc Terry was unlawfully killed.
The jury ruled there was a catalogue of failures not only by the officer who shot Pc Terry but also in the planning, training and safety measures.
Pc Terry, 32, from Burnley, Lancashire, brandished an unloaded handgun during the exercise while playing the role of a criminal fleeing in a car.
He was gunned down by his close friend as the unit practised in a disused factory.
On seeing him holding the gun the officer, granted anonymity during the inquest and identified only as Chris, told the jury he acted "instinctively" and pulled the trigger on his Remington 870 pump-action 12-bore shotgun.
Pc Terry, who was not wearing body armour, was hit from a distance of about 12 inches by a blank round of a specialist ammunition called round irritant personnel, which is not designed to kill but can be deadly at such close range.
Mr Shewan said "a number of changes" had been made to ensure training exercises involving firearms were carried out in the safest way possible since the tragedy.
He added: "I have been in contact with Ian's family since his death in 2008 and once again I would like to extend our deepest apologies to them for loss of their much loved son, father and husband.
"Alongside today's decision there are a further eight officers who still have outstanding misconduct matters against them.
"We cannot make a decision as to when these matters will be dealt with until we have seen the full disclosure files from the HSE for this case.
"Since 2008 GMP has fully co-operated with all of the agencies involved with this and as this is now a HSE prosecution it would be inappropriate for us to make any further comment at this stage."
The HSE said it had concluded there was sufficient evidence and it was in the public interest to prosecute the force and two of its training staff for criminal offences under the Health and Safety at Work Act 1974.
It said summonses would be served on GMP for an alleged breach of Section 2 of the act, on the officer responsible for running the course for an alleged breach of Section 7 of the act and on one of the exercise safety officers, who assisted the lead officer running the course, for an alleged breach of Section 7 of the act.