The outgoing President of the High Court, Mr Justice Nicholas Kearns has said judges should always be mindful of the downstream implications of their decisions.

The judge was speaking during his final sitting as a High Court judge. He is retiring from the bench after 17 years.

Mr Justice Kearns said judges should never put themselves in the position of realising, too late, that a particular decision has opened a Pandora's Box of unintended consequences which if proper consideration had been applied, might have led to a different approach being taken.

He said this was particularly the case where the boundaries of judicial and executive function intersected.   

He also said judges and courts should not be excessively overactive or interventionist.  

Mr Justice Kearns said some felt that successive court interventions had virtually paralysed the investigatory process into matters of serious public concern.  

He said it was not that the courts would intend their decisions would bring about such a situation. But he said, it was the effect of decisions rather than the intention which counted.

Tributes were paid to Mr Justice Kearns by the Chief Justice, Ms Justice Susan Denham, the President of the Court of Appeal, Sean Ryan, the Attorney General on behalf of the Government as well as organisations representing barristers and solicitors, the Courts Service, gardaí and the media.

A lay litigant, paid tribute to the judge "on behalf of the people of Ireland".

Mr Justice Kearns became a barrister in 1968. He was appointed a judge of the High Court in 1998 and he became a Supreme Court judge in 2004 and became President of the High Court in 2009.

Among the high profile cases he dealt with as President were the case of Marie Fleming who was seeking the right to end her own life and the case of a pregnant mother who was brain dead and whose family wanted to be allowed to turn off her life support system.

The judge was due to retire in April next year but retired early to spend some time with his family in New Zealand.

His successor will be Mr Justice Peter Kelly who is currently a judge in the court of appeal and previously presided over the Commercial Court.