A U.S. judge ordered an undecided jury Wednesday to continue its deliberations in the trial of former HealthSouth Corp. (search) Chief Executive Richard Scrushy (search), accused of orchestrating a $2.7 billion accounting fraud at the medical rehabilitation firm.

U.S. District Judge Karon Bowdre issued her instructions one day after the seven male and five female jurors said they could not unanimously agree on a verdict for Scrushy and needed help with the case.

The jury, which began deliberating last week after nearly four months of often complex testimony, had asked the judge to help explain the prosecution's conspiracy charge, considered the linchpin of the case.

"I hope these clarifications help and that you will continue to work hard to reach a unanimous verdict," Bowdre said after explaining that jurors must agree on at least one underlying criminal act to find Scrushy guilty of conspiracy.

Scrushy, a flamboyant 52-year-old millionaire, is also charged with mail and wire fraud, money laundering and other wrongdoing in connection with a sweeping scheme to inflate HealthSouth's earnings between 1996 and 2002.

If found guilty on all the charges, the Alabama native could spend the rest of his life in prison and would join the list of U.S. executives who have been convicted of financial wrongdoing in the wake of recent accounting scandals.

His defense team has been buoyed in recent days by growing signs of a split among the jurors. "We're happy with it," said Charlie Russell, a Scrushy spokesman. "The longer they deliberate the greater the probability they're finding reasonable doubt."