TORONTO — Conrad Black has asked the U.S. Supreme Court to hear his fraud case in a last-ditch effort to overturn his conviction.

The former media mogul wants the country's highest court to review his guilty verdict on fraud and obstruction of justice charges.

His lawyers say the court should assess whether the prosecution's argument, that Black deprived shareholders of the honest services they were owed, is a legitimate one.

Black was convicted last year of a $6.1-million fraud and obstruction of justice related to his eight-year spell as head of Hollinger International Inc.

He's serving a 6 1/2-year prison term in Florida, and had requested a commutation of sentence from U.S. President George W. Bush after unsuccessfully appealing his case.

Black co-defendants John Boultbee and Mark Kipnis are also petitioners, but Peter Atkinson chose not to be included.