Former Worldcom boss Bernie Ebbers, who was found guilty of fraud and conspiracy in connection with the biggest ever US corporate bankruptcy, has called for a new trial.
Ebbers, 63, is claiming he was treated unfairly in court first time around.
His legal team are claiming the judge should have
given immunity to three executives whose testimony, had they been able to appear, could have helped to clear Ebbers.
Those Worldcom employees could have taken the 5th Amendment, Ebbers claims, to ensure their own protection from prosecution - but they ultimately did not testify in the case.
Ebbers also says the jury were faced with too many wide-ranging decisions, which made his conviction a more likely outcome.
About 20,000 workers lost their jobs and shareholders lost close to US$180bn when Worldcom collapsed in 2002 in one of the US's biggest business scandals this decade.
$11bn of shareholders' funds were missing from its accounts.
Ebbers has always pleaded that he was ignorant of all the fraudulent goings-on, and blamed the fraud on Scott Sullivan, his former CFO at Worldcom.
Ebbers is scheduled to be sentenced in June.
