Auditor general Michael Ferguson's review concluded that Sen. Pierre-Hugues Boisvenu didn't spend enough time in Sherbrooke, Que., in 2012 to make that his primary residence.
In his response, which was contained in Ferguson's report, Boisvenu said he was in the midst of separating from his wife during the audit period, which is why he spent more time in Ottawa than in Sherbrooke.
Ferguson also found that Boisvenu travelled the country doing interviews and events for his foundation, which is focused on helping victims of crime.
Boisvenu said he was travelling on parliamentary business and representing the government at events in Quebec to push the Conservative's law-and-order agenda. His book just happened be on sale at some of those events, he said, but that all the revenue when to a scholarship fund named in his daughter's honour.
He also insisted that the Senate rules don't require senators to live at their primary residences for a minimum amount of time.
Boisvenu said he wants to challenge the findings in the arbitration process set up by the Senate and headed by former Supreme Court justice Ian Binnie, in order to get a definition of "parliamentary business."
The arbitration process is open to every senator named in the report, including the seven retired senators and two current ones — Boisvenu and Senate Liberal Colin Kenny — referred to the RCMP for a criminal review.
Boisvenu quit the Conservative caucus last week after news broke that his expenses were being referred to the Mounties.
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