A Londonderry solicitor who advised Saddam Hussein's defence team said the court which sentenced him to death was a "completely illegimate creation".
Saddam Hussein remained defiant throughout his sentencing
Saddam Hussein was convicted over the killing of 148 people in the mainly Shia town of Dujail following an assassination attempt on him in 1982.
But lawyer Des Doherty said the court functioned like an "illegal marshland" and "flew in the face of legal logic".
Mr Doherty said dealing with the trial solely in Iraq "was a mistake".
"An international court may not have given the Iraqi people the ownership of the situation they wanted, and, some would say, perhaps deserved," he said.
"But it would, at least, have given a sense of legitimacy and independence and impartiality which was so obviously lacking in the course of the trial."
Mr Doherty said his role was to advise the lawyers who were dealing with the day to day running of the trial about the legitimacy of the court.
He said the law under which the court had proceeded did not stand up to international scrutiny.
"This court was a completely illegitimate creation, mainly created by the American and British authorities," he added.
"It is not a complete Iraqi court. All the work that goes on and all the judgement that was made was really handed down, as far as we can see, by the Americans."
Mr Doherty said that the court had been "largely funded by the US and heavily staffed by US personnel".
"If Britain and America are bringing this great democracy, the rule of law and justice to the world, an essential part of that is a proper legal system," he said.
"This court is not lawfully mandated by the UN, it functions like an illegal marshland of its own creation."
Mr Doherty has been involved with the Bloody Sunday Inquiry
Mr Doherty was also involved in the Northern Ireland Bloody Sunday inquiry into the deaths of civilians on a protest march in Derry in 1972.
He said that inquiry, which sat in the Guildhall in Derry, was different in that it did not deal with criminal matters.
"The Bloody Sunday Tribunal was a non adversarial, inquisitorial process. Iraqi law is supposed to be non-adversarial and is supposed to be inquisitorial," he said.
"The statute which governs the Iraqi Special Tribunal was essentially drafted by American advisers. It was drafted in terms of being adversarial and confrontational, so it completely flew in face of legal logic for Iraqis."
Saddam Hussein's half-brother Barzan al-Tikriti and Iraq's former chief judge Awad Hamed al-Bandar were also sentenced to death by the same court.
Saddam Hussein and his co-defendants will be given the right to appeal, but that is expected to take only a few weeks and to end in failure for the defendants.