Fallen media baron Conrad Black had harsh words for the American judges hearing the appeal of his fraud conviction, saying they don't understand the case and sometimes acted like part of the prosecution.

Black made the comments in an e-mail sent to the Globe and Mail from the Coleman minimum-security prison where he has been serving his 6½-year sentence since March.

"As you will have noticed, [Judge Richard] Posner and [Judge Diane] Skyes had little understanding of the case and were, in a way that I am unfortunately familiar with, essentially part of the prosecution until the realization began to dawn that they didn't really understand the case," the Globe and Mail quotes Black as writing.

The two judges with the Seventh Circuit Court of Appeals in Chicago were among three that heard oral arguments last week on appeals filed by Black and his co-defendants to try to overturn their convictions.

The Montreal-born Black, 63, and his three co-accused — John Boultbee, Peter Atkinson, Mark Kipnis —  were convicted of mail fraud for defrauding shareholders of newspaper company Hollinger International Inc., while Black faced an additional count of obstruction of justice.

Black also expressed little optimism about his chances of a successful appeal in the e-mail.

"After all I have endured over the last five years at the hands of the trans-border justice system," Black writes, "I would have to be insane to predict anything too positive."

If his appeal fails, Black can take the case to the full nine-judge appeals court and eventually ask for a review by the United States Supreme Court.