Mike Duffy's lawyer demanded proof today from the former chief of Senate finance that Senate administration had a policy that prohibited senators from charging travel expenses for all fundraising activities.

Donald Bayne grilled Nicole Proulx on that point after she testified that expensing travel in relation to fundraising activities, while not explicitly covered in the Senate administrative rules, was "something that's not allowed either for political purposes or charity."

"Where does it say this? Show us," Bayne asked Proulx. "I want you to show us some evidence where this is written."

"Where does it say fundraising activities are prohibited partisan activity? Where does it say that?"

The trial, in its 16th day, began April 7 in an Ottawa provincial courtroom. 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 provided by the prime minister's former chief of staff Nigel Wright.

Among the charges, Duffy is accused of expensing travel for partisan political events.

Proulx said that part of the fundraising travel expense policy could be found in the miscellaneous expenses guidelines. But she said the policy was later clarified by a Senate steering committee.

Proulx said this policy was in place before she was at Senate finance. She added that she was told about the policy by a manager in the department who had consulted with a member of the Senate committee.

But Bayne argued that the miscellaneous expense guidelines had nothing to do with travel and that the Senate committee opinion was all hearsay.

"You are able to show no evidence of any written notice to senators of these hearsay conversations that [the manager] had that you subsequently had, right?"

Proulx said that with the information she had in front of her, she couldn't answer.

"I would have to look, but as it stands now I cannot offer anything," Proulx said.

Earlier, Bayne grilled Proulx on the issue of expensing senators' travel claims for partisan business, arguing that there are virtually no rules governing such activities and that the whole administrative system lacks oversight.

"The system you've set up deliberately creates a system where you don't ask questions," Bayne said, on his third day cross-examining Proulx.

Bayne argued that the Senate administrative rules explicitly state that partisan activities are an essential part of a senator's duties. And nowhere in those rules does it define the term "partisan," he said.

In terms of limitations on expensing partisan activities, the rules only state that senators can't expense costs related to the election of a member of the House of Commons, Bayne argued.

But Proulx refused to concede that only the administrative rules govern the actions of the senators.

"I just need to say that the [administrative rules] are supplemented by policies, guidelines, opinion, directives, forms and practices adopted or implemented by [the Senate]," she said.

"​So these policies, once they are adopted, complement, supplement, so we have to apply those as well."

​Proulx has spent three days under cross-examination, defending Senate administration rules and regulations while denying she has any bias relating to the case of the suspended senator.

On Monday, court learned the existence of an unpublished 2013 internal audit on Senate residency that Bayne might want to put into evidence. Details of this audit have not been made public, and the Senate has served notice it will assert privilege, meaning its findings will remain secret.

Meanwhile, Bayne spent a significant portion of time reviewing the rules of primary and secondary residency.

Residency central issue

Residency is one of the central issues in the case against Duffy. He designated his home in P.E.I. as his primary residence, and he maintains that's the case, making him eligible to claim meals and living expenses for his time in Ottawa.

The Crown disputes that Duffy's primary residence is in P.E.I. The suspended senator has lived in Ottawa since the 1970s.

​Bayne has argued that the various rules and regulations guiding senators provide no clear definition on the term "primary residency." On Monday, Bayne argued that Senate finance officials signed off on Duffy's expenses to live in Ottawa, even though they had been informed he had been living in his Kanata home for seven years.

Proulx said she didn't recall having that information brought to her at the time but agreed that there were no definitions or criteria clearly laid out for establishing "primary" or "secondary" residence. 

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