Senator Pamela Wallin is preparing to fight a bid by her former party to have her suspended without pay — a gambit her lawyer calls an affront to Canadian democracy designed to help the Conservatives change the channel.

"It is backroom politics at its transparent worst and it's designed to create the impression of a clean slate for the Tory convention in Calgary next week," lawyer Terrence O'Sullivan said in an interview Friday.

Senate motions are set to be debated 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.

But O'Sullivan, who represented Wallin throughout the process, said neither the audits nor any document passed by the Senate has used the phrase "gross negligence," a specific legal term.

"It's a fundamental affront to Canadian democracy," O'Sullivan said.

Wallin has also never been criminally charged, and has not been contacted by the RCMP.

O'Sullivan said that minutes of Senate meetings about Wallin and of meetings with the auditors from Deloitte have never been released. He also described being invited to one particular meeting at which he was not permitted to speak.

Wallin has repaid $140,000 in travel expenses, but said at the time she said she disagreed with the accounting principles used by the auditors.

Asking her to defend herself on the floor of the Senate on the subject of hundreds of contentious expenses is unfair, O'Sullivan said.

"People in Saskatchewan shouldn't be deprived of a senator without a hearing and she shouldn't be deprived of two years of livelihood without a hearing. We will offer to the Senate to attend a full public hearing."

The Senate's own rules underline the presumption of innocence when a senator is charged with a criminal offence, he added — a concept echoed in the Charter of Rights and Freedoms that O'Sullivan said he believes applies to all accusations.

"They're constrained by the sense of due process under the charter, unless they say they don't care about due process and they don't care about the Charter of Rights, and that they can do what they want," said O'Sullivan.

"Do you know what that means? That means that what we have here is the equivalent of a third-world dictatorship sending its political irritants into exile. This doesn't happen in Canada, this shouldn't happen in Canada."

Wallin's lawyer is also arguing that effectively removing a senator for up to two years contravenes the Constitution because Saskatchewan has a right to a certain number of representatives.

If Wallin was forced to resort to the courts, it would be a closely watched and likely hard-fought battle.

The independence and primacy of Parliament is a tenet of the Canadian system, with senators and MPs jealously guarding their right to make their own rules as they see fit.

A handful of Liberal senators and at least one Conservative have expressed reservations about allowing the upper chamber to exercise its power the way it seems to be doing.

Adam Dodek, vice-dean at University of Ottawa's law school, said there's no doubt in his mind that the Senate is within its rights to suspend the senators. Whether it's prudent is another matter entirely, he said.

"It gets to the point of recognizing how much power the Senate and the House of Commons have, and I think that the concern is that once you start disciplining and suspending people short of there being criminal charges laid, then where do you draw the line?" Dodek said.

"The concern would also be about potential use of that power for partisan purposes."