Garda Commissioner Noel Conroy has said the culture within An Garda Síochána must become more "open".
He also warned members that closing ranks when problems arose only led to further difficulties.
While recommendations in the Morris tribunal reports were already being acted upon, he believed some members who had left the force after being criticised by Mr Justice Frederick Morris had previously been "good servants" of the State.
"Unfortunately we lost some people," he told the Garda Review magazine which is published by the Garda Representative Association (GRA).
"Some people seemed to be doing a very good job but they were found by the tribunal not to have acted professionally . . . They had been good servants of the people for many, many years."
He added that if some members had been more truthful in the early stages of the investigation into practices in the Donegal division "many of the problems that we are having today would not have been there."
"Our major problem is when we do make mistakes and we close all doors and six, nine or 12 months later this is disclosed and it becomes a major problem. Morale will be affected eventually."
He said older members had been most affected by the tribunal's findings. Younger gardaí were not in the force when events now under investigation were unfolding and so "they do not identify with it".
He was in agreement with Mr Justice Morris that disciplinary problems were not confined to the Donegal division. However, he stopped far short of agreeing that indiscipline was a problem throughout the force.
"We have experienced it in different parts of the country, but I want to emphasise that it is not a major problem. It is not a major problem throughout the country."
He added that while a small number of members shouted loudly when being investigated most other gardaí had no interest in what these individuals were shouting about.
He believed the Garda Ombudsman and Garda Inspectorate would prove positive influences in the unprecedented change process now under way. He would be fully co-operating with both. He believed that while some media comment had been selective and unfair journalists had an important role to play.
"If we are wrong we are wrong and the media should report it. The media has done good for this country; there is no doubt about that either."
He also urged members of the force to be fair in their dealings with Garda reservists telling them to form their own opinions in time. Reservists represented another facet of vital community support for full-time members.
While some members believed the promotion system within the force at times did not work, he believed it to be transparent.
Under changes already being implemented there would only be one member of An Garda Síochána on interview boards in the future. He said he had no problems with this.
Elsewhere in the magazine the GRA's executive member for Donegal Michael O'Boyce called for changes to the force's promotion system.
He believed the current mechanisms were based on "patronage, cronyism and nepotism". Some in Garda management were solely focusing on promotion, with duty to the public becoming secondary.
He believed the Department of Justice's control of promotions at the top of the force served Government manipulation well. This would only change when a new Garda authority was created which was responsible for appointing the Garda commissioner.
