Because they just don't care about law and justice any more than he did. As Reuters AlertNet reports it:
The trial of Saddam Hussein and seven other defendants before the Iraqi High Tribunal for crimes against humanity was marred by so many procedural and substantive flaws that the verdict is unsound, Human Rights Watch said in a 97-page report released today. 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 proceedings in the Dujail trial were fundamentally unfair," said Nehal Bhuta of the International Justice program at Human Rights Watch and author of the report. "The tribunal squandered an important opportunity to deliver credible justice to the people of Iraq. And its imposition of the death penalty after an unfair trial is indefensible."
