An Air Force officer was convicted by a military court on a charge related to the Anzac Day helicopter crash that killed three airmen.
The flight authorising officer was convicted for failing to comply with written orders - but the conviction was later overturned on appeal.
The officer is the only one to have been charged so far in connection with the fatal crash of an Iroquois at Pukerua Bay on Anzac Day 2010 as it and two others headed to a dawn flypast in Wellington.
It is understood more charges loom as the air force provost marshal's investigation into the crash nears completion.
An earlier court of inquiry, conducted by the Defence Force, reported its findings in December, and noted errors committed by the Iroquois pilots within inadequate Defence Force protocols.
But while that inquiry set out to uncover facts, the provost marshal's investigation seeks to decide whether any blame should be attributed.
It is understood that the flight authorising officer was charged in June last year, convicted at a summary trial, and that the conviction was overturned in September.
A letter issued last week from air force chief Air Vice-Marshal Peter Stockwell to families of the crash victims said the provost marshal's investigation was almost complete.
"At this stage, no decision has been made as to whether any charges will be laid," the letter said.
But a source close to the Defence Force said "another person" may face charges.
Group Captain Russell Sowden, the provost marshal investigator, said a "number of recommendations" from his report were being considered by the air component commander, Air Commodore Steve Moore.
It was up to the air commodore to decide whether the recommendations were pursued as prosecutions.
"There's a whole process to go through and the investigation was but one part of that," Group Captain Sowden said.
It is also possible that criminal charges may follow, with the father of one of the dead airmen pressing for police to lay manslaughter charges.
Andrew Carson, whose son Ben died in the crash, said: "I still intend at some stage to go to the police and lodge a complaint because . . . no-one has been held accountable."
He wanted the pilot from the lead helicopter charged and wanted Air Vice-Marshal Stockwell and former air vice-marshal Graham Lintott to face corporate manslaughter charges.
Sergeant Stevin Creeggan, the sole survivor of the crash, has also engaged a prosecution against both the Defence Force and the chief of defence for failing to protect his welfare in the workplace.
Summary trial: Minor military matters may be charged in a summary trial. The normal rules of evidence are replaced by a simpler formulation and lawyers are excluded.
Penalties vary, but in most cases include: a maximum of 28 days' detention, a reduction in rank, a fine not exceeding 28 days' pay, a reprimand, extra duty not exceeding two hours a day, and a caution.
Court martial: For offences considered more serious. It covers military criminal jurisdiction. A judge always presides and is joined by a panel of three to five military members.
Punishments are more serious, including imprisonment for life.
- The Dominion Post