The Health and Safety Executive (HSE) will charge Greater Manchester Police and two officers over the shooting of PC Ian Terry in 2008.
Terry, 32, from Burnley, was killed when he was shot in the chest by a colleague during a police training exercise.
Although the Crown Prosecution Service had said there was insufficient evidence to press criminal charges, the HSE found there was enough evidence to prosecute the force and two officers for breaching health and safety laws.
Assistant chief constable Garry Shewan confirmed the HSE prosecution will go ahead.
He said: "I have been in contact with Ian's family since his death and once again would like to extend our deepest apologies to them for loss of their much loved son, father and husband.
"Since Ian's death we have made a number of changes to the way in which we train officers to ensure that all firearm training exercises are carried out in the safest possible way by reinforcing procedures and existing policies."
An inquest held at Manchester coroner's court in March 2010 recorded a verdict that Terry was unlawfully killed.
The father-of-two was shot in June 2008 as he brandished an unloaded handgun while playing the role of a criminal during a training exercise at a disused warehouse in Newton Heath, Manchester.
He was not wearing any body armour and was shot from about 30cm (12in) by a fellow officer using a round of ammunition called round irritant personnel. While the ammunition is not designed to kill, it can be fatal at close range.
The officer responsible for shooting Terry was granted anonymity for the inquest. At the time, he told the jury that he acted "instinctively" before pulling the trigger on his Remington 870 pump-action 12-bore shotgun