A decision of the Medical Council and its Fitness to Practise Committee has been quashed by the President of the High Court.
The committee had found Dr Samuel McManus guilty of professional misconduct.
Mr Justice Nicholas Kearns said that while Dr McManus had accepted responsibility for wrongly altering a patient's medical notes while he was a senior house officer in Dublin's Mater Hospital, he had not been afforded fair procedures during an inquiry.
Mr Justice Kearns said the importance of adhering scrupulously to the requirements of fair procedures was central to the proper conduct of disciplinary processes, which might result in serious sanctions for the person concerned.
He said the inquiry was a matter of the utmost gravity to Dr McManus, a doctor with a hitherto unblemished record.
He said the imposition of any finding of professional misconduct or sanction with all its adverse career consequences could be justified only under scrupulously fair procedures.
Judge Kearns, in a reserved judgment, said that in April 2008 a man had been found hanging from his shoe laces on a shower rail in the Mater Hospital and died a fortnight later.
He had earlier attempted to take his own life by throwing himself into the River Liffey.
The judge said Dr McManus, 32, had accepted he altered clinical notes of the patient following the suicide attempt in the hospital and a number of allegations of professional misconduct had been made against him.
The Fitness to Practise Committee had recommended a sanction of admonishment in a report following an inquiry, but the Medical Council had imposed the lesser sanction of "advice".
Judge Kearns said that at the end of the day the plain fact of the matter was that Dr McManus had altered medical records and had fully admitted doing so and had further accepted that the changing of notes was inappropriate.
He said that however inconvenient and burdensome it may be to write up medical records accurately, such records constituted a vital safeguard for both medical practitioners and patients alike in any situation where it later became necessary to conduct any form of investigation as to what transpired during the course of a patient's treatment.
"Every practitioner must be taken as knowing that records may later be used in court proceedings or other investigations or inquiries and hence their importance is self-evident," Judge Kearns said.
He quashed all decisions that had been reached by both the Medical Council and its Fitness to Practise Committee.
