Siegelman's attorney Sam Heldman said the appeal questions whether a campaign contribution can be used for a bribe. The appeal also questions whether there must be an explicit quid pro quo if a campaign contribution is offered as a bribe. Siegelman is appealing the latest decision of the 5th U.S. Circuit Court of Appeals that threw out two charges, but turned down much of his appeal.

Siegelman's appeal to the Supreme Court seeks to clarify for all candidates for public office whether a campaign contribution can be used as a bribe.

"Money is the lifeblood of modern politics and most if not all officials are responsive in at least some degree to those who contribute," Siegelman's attorneys wrote in their filing.

Prosecutors said Siegelman appointed former HealthSouth CEO Richard Scrushy to an important hospital regulatory board in exchange for Scrushy arranging $50,000 in contributions to Siegelman's campaign for a statewide lottery.

The appeal questions how the case could affect elected officials nationwide who appoint campaign contributors to positions in their administrations.

Siegelman has served nine months of a more than seven-year federal prison sentence. He is currently free on an appeal bond and faces a new sentencing hearing if the Supreme Court turns down his appeal.

Scrushy had a new sentencing hearing last week before U.S. District Judge Mark Fuller. Fuller shaved a year off his original sentence of almost seven years. Scrushy has already served more than four and a half years in prison and is expected to be eligible to transfer to a halfway house within the next few months.

Heldman said he expects a decision by summer on whether the Supreme Court will hear Siegelman's appeal.

Laura Sweeney, a spokeswoman for the U.S. Justice Department, said prosecutors would have no immediate comment about the appeal.

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