CNN

I. Lewis "Scooter" Libby arrives at the courthouse on Thursday for his hearing.

WASHINGTON (CNN) - A federal judge on Thursdayordered I. Lewis "Scooter" Libby to report to prison to serve his sentence while his attorneys appeal his case.

In trying to delay the sentence, defense lawyers tried to convince U.S.District Judge Reggie Walton that there was a good chance they could overturn Libby's conviction on appeal

Libby has been free since he was convicted March 6 of perjury and obstruction of justice for hindering a FBI and grand jury investigation into how the name of CIA operative Valerie Plame Wilson was leaked to the media.

No one has been charged with leaking classified information in the case,

Cheney's former chief of staff, who maintains he is innocent, was sentenced to two and a half years in prison and fined $250,000.

– CNN's Paul Courson and Debra Krajnak