Ontario Justice Charles Vaillancourt is hearing arguments about whether a particular Senate committee report can be considered fact for the purposes of the suspended senator's trial.
The 2010 document prepared for the internal economy committee is heavily based on the result of three audits conducted for the Senate by the firm Ernst & Young.
The content of the report is important to Duffy's defence because it points to systemic problems in Senate administrative practices.
Duffy has pleaded not guilty to 31 counts of fraud, breach of trust and bribery, most of which relate to living and travel expenses and to Senate contracts he arranged. Much of his defence so far has focused on the lack of clarity in the Senate rules, and the argument that he is only guilty of making administrative mistakes.
"Although a definition of a parliamentary function exists within the SARs (Senate Administrative Rules), there is a lack of clear guidelines and criteria clarifying what activities constitute a parliamentary function," reads the Senate report.
"For example, there is no clear guidance made between partisan activities relating to Senate business (allowable expenses) and partisan activities on behalf of political parties which may not be eligible."
The Crown is expected to argue that the report should only be treated as opinion or heresay, because it is based on the work of outside individuals.
Defence lawyer Donald Bayne is arguing that while the report is based on Ernst & Young audits, it went through three separate layers of validation, consideration and approval at the Senate and should be considered a product wholly of the committee.
As a Senate committee report, Bayne says it meets the test for being treated as an official public document under the Canada Evidence Act. He cited a 1996 Ontario Court of Appeal decision in which four criteria are laid out for the admissibility of evidence as a public document in court, and said the report meets all of them.
"There is inherent reliability in the fact of it being a public document," Bayne said.
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