OTTAWA -- Sen. Pamela Wallin is threatening a legal battle against a Conservative move to suspend her without pay -- something her lawyer calls an affront to Canadian democracy.

Senate motions are set to be debated next week that would suspend Wallin, Mike Duffy and Patrick Brazeau for "gross negligence" for the rest of the parliamentary session, which could last two full years.

The three former members of the Conservative caucus were found by the Senate to have filed improper expense claims following independent audits.

Wallin's lawyer Terrence O'Sullivan says there is nothing in the audits or the resulting Senate reports that make any mention of gross negligence.

O'Sullivan says the Senate's own rules and the Constitution require due process, something he says Wallin has been never afforded during a series of in-camera hearings.

He says if the motion against Wallin is passed, Saskatchewan will be denied its constitutional right to one of its senators, a move he attributes completely to political expediency by the Conservatives.