06/08/2015 08:33 EDT | Updated 06/08/2016 05:59 EDT

Mike Duffy Trial: Former Office Staff Of Suspended Senator Set To Testify

The Mike Duffy trial is expected to hear today from former staff members of the suspended senator's Senate office.

​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 former chief of staff, Nigel Wright. The trial, which began April 7 in the Ontario Court of Justice in Ottawa, is into its 28th day. 

Court has previously seen emails and heard testimony of exchanges between members of Duffy's staff and Senate administrative officials over Duffy's senate contracts and some expenses.

This week, lawyers are also expected to spend one or two days arguing 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's defence lawyer Donald Bayne believes the report will support his argument that the rules of the Senate are vague and ambiguous.

The argument over the 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 this week.

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