Lawyers for the Senate are scheduled to appear before an Ottawa judge Wednesday morning to argue that Senator Mike Duffy cannot sue the upper chamber over his dramatic suspension without pay five years ago.

Duffy is seeking more than $7.8-million in damages from the Senate and the RCMP, in the wake of the high-profile investigation and suspension surrounding his expense claims.

Duffy stood trial and was acquitted on 31 charges in April 2016.

The portion of the lawsuit against the Senate hinges on Duffy’s arguments that senators acted unconstitutionally and violated his charter rights when they decided to suspend him without pay in 2013.

The Senate will argue that the court has no jurisdiction to judge the decision senators made to suspend Duffy without pay for almost two years, citing parliamentary privilege, a centuries-old right designed to protect legislators in the course of doing their jobs.

If the court agrees with Duffy, he would only be able to sue the federal government for the RCMP’s actions during its investigation.

The Senate restored Duffy as a member of the Senate in full standing within hours of the verdict in 2016.