Terming the trial of ousted Iraqi President Saddam Hussein as 'flawed', a US-based human rights groups has accused the Iraqi government of influencing the judges.
Hussein was sentenced to death on November 5 after being convicted for crimes against humanity.
The trial by the Iraqi High Tribunal was marred by so many 'procedural and substantive flaws' that imposition of death penalty is 'indefensible', Human Rights Watch said, adding that the verdict was 'unsound'.
"The proceedings in the Dujail trial were fundamentally unfair," Nehal Bhuta of the International Justice programme at Human Rights Watch and author of the 97-page report released on Sunday said.
'The tribunal squandered an important opportunity to deliver credible justice to the people of Iraq. The Iraqi High Tribunal was undermined from the outset by Iraqi government actions that threatened the independence and perceived impartiality of the court.
'Members of Parliament and even ministers regularly denounced the tribunal as weak, leading to the resignation of the first presiding trial judge', it noted.
The shortcomings of the trial, for the killings of more than 100 people from the Iraqi town of Dujail, also call into question subsequent proceedings at the tribunal, the report said.
The report also said that the tribunal as an institution has struggled to 'competently perform basic administrative functions' that are essential to a fair and effective trial.
'It failed to develop effective programmes to address the needs of witnesses and victims or to ensure the security of defence lawyers, and ignored the important task of explaining the trial process to the Iraqi population', it added.
"The tribunal failed to meet basic fair trial standards in its first trial. Unless the Iraqi government allows experienced international judges and lawyers to participate directly, it's unlikely the court can fairly conduct other trials," Bhuta said.
The Dujail trial commenced before the Tribunal in Baghdad on October 19, 2005, and ended on July 27, 2006, with the verdict announced on November 5, 2006.
Saddam Hussein and two other defendants were sentenced to death by hanging, and four defendants received prison terms ranging from 15 years to life.
One defendant was acquitted at the prosecution's request.
The verdict and sentences are currently being appealed to the Appeals Chamber. The trial concerned the aftermath of an assassination attempt against then-President Saddam Hussein in Dujail in July 1982.
Government officials were accused of orchestrating an attack on the town's inhabitants in revenge for the assassination attempt, resulting in the detention, torture and forced displacement of hundreds, and the deaths of more than 100 boys and men after a summary trial.
