06/11/2015 08:36 EDT | Updated 06/11/2016 05:59 EDT

Mike Duffy trial: Lawyers to argue over secret internal Senate report admissibility

Lawyers at the Mike Duffy trial in Ottawa will argue today over whether details of a 2013 internal Senate audit on the residency status of senators are admissible.

The issue is whether the Senate has the right to assert parliamentary privilege over this report, meaning its details would be kept secret from the public.

Duffy has pleaded not guilty to 31 charges of fraud, breach of trust and bribery related to expenses he claimed as a senator and later repaid with money from the prime minister's then chief of staff Nigel Wright. The suspended senator's trial, which began April 7 in the Ontario Court of Justice, is in its 31st day.

Duffy's defence lawyer, Donald Bayne, wants the report entered in as evidence, believing it will support his argument that the rules of the Senate are vague and ambiguous. The audit was conducted by Jill Anne Joseph, then director of internal audit at Senate administration.

Residency is one of the central issues in the case against Duffy. He designated his home in P.E.I. as his primary home, making him eligible to claim meals and living expenses for his time in Ottawa, even though he has lived and worked in Canada's capital since the 1970s.

The Crown in Duffy's trial disputes that P.E.I. is his primary residence and contends that Duffy was not eligible for those claims.

The argument over the Senate report, one of the types of legal side issues that has helped extend the length of the trial, was supposed to have been made when the second phase of the trial resumed last week. But the issue was postponed until now.