Embattled media baron Conrad Black has come to the defence of his wife, urging prosecutors to leave her out of his U.S. trial.

In a court filing made available on Wednesday, and first published by The Globe and Mail, Lord Black argues that the personal shopping habits of Barbara Amiel-Black have no bearing on his criminal trial in Chicago.

Prosecutors have alleged Black used Hollinger International Inc. to pay for a variety of personal expenses including $2,500 in handbags for Lady Black.

They also claimed that in 1998, Lord Black and others engaged in illegal insider trading with the help of Brascan Corp. in Toronto, in order to boost Hollinger's share price.

"The defendant in this case is Conrad M. Black, not his wife, Barbara Amiel-Black. That International may or may not have paid for certain shopping expenses on her behalf is not an "other act" of Mr. Black," the filing states.

The filing goes on to say that the prosecution's motion to bring Lady Black into the trial doesn't prove Black himself was aware of, or authorized, her shopping, and as a result should not be admitted against him.

The filing also suggests Amiel-Black "has sometimes been a lightning rod of controversy" and suggests her involvement would create a "circus-like sideshow."

Black, along with three other former Hollinger executives, is alleged to have taken more than US$80 million from the Chicago-based newspaper company.

All four have pleaded not guilty and none of the allegations have been proven.

The allegations included in the recent filing are not directly linked to the criminal case against Black.

Instead, they are intended to prove Black and his associates were involved in other "bad acts."

In the filing, Black also dismissed prosecutors' allegations that he posted messages on the Yahoo Finance message board responding to questions about Hollinger's stock.

Black said all of the new allegations are irrelevant to the criminal case and should not be allowed because they will confuse the jury, complicate the case and lengthen the trial, which is set to begin in March.