An actor best known for appearing in the BBC hospital dramas Casualty and Holby City said he was "utterly shell-shocked" after two men were cleared of an attack on him in which part of his ear was bitten off.
Clive Mantle said it was worrying that violent acts go unpunished after a jury cleared the men of GBH with intent and the lesser charge of GBH a jury.
Philip McGilvray, 33, admitted biting the 6ft 5in actor's ear after they clashed in a Newcastle hotel corridor in a late-night row over noise last March, but claimed self defence.
He and his friend Alan French, 32, also from Hamilton, Scotland, were cleared by a Newcastle crown court jury which deliberated for almost five hours.
Mantle, who also appeared in the hit US show Game of Thrones, said in a statement: "I am utterly shell-shocked by the verdict of the court, and have lost a great deal of faith in a process which can deliver such an injustice.
"As much as I am hurt and baffled by the decision, I am more worried at the message it gives out to law-abiding people who dare to point out the terrible behaviour of others. Are we all just meant to sit back and not say anything? The fact that violent acts go unpunished is equally worrying."
The actor, who was appearing in a touring production of The Ladykillers at the time of the incident, was woken in his Travelodge room by repeated shouting in the corridor outside. He went to summon security when there was a clash in which the three men ended on the floor, and the actor's ear was severed. McGilvray, who had been out drinking with friends since the afternoon, claimed he was acting in self defence after the actor charged at him and knocked him to the floor.
He told the jury: "I turned around and the next thing I was taken out by this big guy. I'm not sure if he punched me or clothes-lined me.
He could not move because "I had a big monster on me" who he thought was trying to kill him and believed he had no alternative but to bite Mantle's ear, the court heard.
While giving evidence in the trial, Mantle had shown the jury the extent of his injuries, lifting the hair he has grown long over his ears to show a missing part.