The controversial move to axe PSNI reserve officers is to be challenged in the courts.
Officers' representative body, the Police Federation, has lodged papers with the High Court in Belfast seeking a judicial review.
Chief Constable Sir Hugh Orde is set to push ahead with phasing out the Full Time Reserve by March 2011 as part of policing reforms.
The legal challenge is to be made on the grounds that the Chief Constable did not consult sufficiently with the federation before pushing ahead with the decision.
Federation chair Terry Spence also said Sir Hugh Orde - who is leaving his post in September - should have left the decision to his successor.
"The decision to terminate the services of 500 Full Time officers defies the principle of consultation with this staff association on matters which fall directly within our statutory remit of welfare and efficiency," he said.
"It is also a decision which flies in the face of an enduring severe terrorist threat, a volatile public order situation as demonstrated throughout Northern Ireland over the Twelfth parades and a significant increase in serious crime."
Established at the start of the Troubles, the full-time reserve had 3,500 members at its height.
Thousands of officers have already been stepped down from service as part of the Good Friday Agreement's Patten policing reforms while the part-time reserve has also been disbanded.
The judicial review hearing is expected to be heard in September - at which stage Sir Hugh will have left the PSNI - after seven years in charge - to become president of the Association of Chief Police Officers.
A PSNI spokesman said it would not be appropriate to comment on the legal challenge at the present time.
In defending his decision last month, Sir Hugh said the Patten reforms were "non-negotiable".
"We are satisfied that, in the longer term, the correct response must be to proceed with the phasing out of the Full Time Reserve and to use our regular officer establishment properly, with police officers doing policing jobs," he said.
A total of 102 reserve officers lost their lives during the Troubles.
Announcing the move, Sir Hugh paid tribute to all those who had served in the Reserve.
"The people of Northern Ireland owe a tremendous debt of gratitude to the men and women of the Full Time Reserve and indeed their part-time colleagues," he said.
© Press Association