When the court martial resumed after two hours' consideration of its verdict, it took the President of the court, Col Sean Brennan, only two minutes to read it.
There were no preliminaries before he read out Comdt Byrne's full name, rank and number and said: "Guilty of the charge, subject to confirmation by the convening officer. You will be informed of your right to appeal." Comdt Byrne, already of ruddy complexion, flushed a deeper red and stared fixedly at the table in front of him.
The first character witness, his immediate superior in Lebanon, Comdt John Hamill, was pale as he came to give evidence, speaking of "other agendas at work" concerning the relationship between Comdt Byrne and certain other officers.
There was a brief recess while waiting for the second character witness, Col Desmond Travers. Outside the courtroom the commandant's wife, Peggy, his son, Anthony, and two daughters were waiting in a room set aside for the defence. He joined them briefly, before re-emerging to hear the sentence. He muttered: "I can take it. It's those people inside." There was sobbing from the room.
In the courtroom Col Travers started to give evidence of Comdt Byrne's character, but his words were drowned by distraught weeping from the corridor outside. A few moments later an ambulance drew up outside the building. Mrs Byrne had collapsed in the hall. She was comforted by friends from the Holy Family Sisters in the Curragh, and the ambulance was sent away.
By a strange coincidence, the cheerful sound of an Army band in the distance also permeated the courtroom. Yesterday saw the first official visit of the new Minister for Defence, Mr Smith, to the Curragh, and he was being welcomed by a guard of honour and a band.
After the sentence was announced Mrs Byrne was led weeping from the building, leaning heavily on the arm of a nun and on one of her daughters, also in tears.
"You print the truth about my husband. It's a disgrace," she said.
Her son, Mr Anthony Byrne, said: "You're talking about a man who's served the Army loyally for 35 years. They're saying that after 35 years he decided to disobey an order."