The damaging report is the culmination of more than two years of controversy over senators' expenses, a scandal that has brought down a number of senators, spurred RCMP investigations and court proceedings and now promises to bring more scrutiny to even the most powerful figures in the upper chamber.
The auditor general's office investigated the expense claims of current and former senators going back a number of years, and found 30 with inappropriate expenses totaling more than $975,000. The ineligible expenses ranged from a few thousand dollars to more than $175,000 for the highest spender, retired Manitoba Liberal Senator Rod Zimmer.
Nine of the cases, including those of sitting senators Pierre-Hugues Boisvenu and Colin Kenny, have already been sent to the RCMP for possible investigation.
The auditor general's report was delivered to the Senate on Thursday, giving staff several days to craft responses to the findings. An email from Senate Opposition Leader James Cowan to members of the Senate Liberal caucus, obtained by CBC News, said "talking points" would be made available to senators during their meeting on Tuesday, before the report's release to the public.
The auditor general is also expected to make several recommendations to change the Senate's expense rules. In anticipation, the Senate has already ended the practise of providing meals at committee meetings and will bring in changes to its travel policy to restrict business class flights after the end of the current sitting.
Speaker Leo Housakos is expected to address the media in the foyer of the Senate at 2:15 p.m. ET, shortly after the report is released.
At 3:45 p.m. ET, the auditor general will hold a news conference in Ottawa to discuss his findings. CBCnews.ca will carry both events live.
On Monday, Housakos and Cowan announced they are reimbursing the full amount of their contested expense claims, about $6,000 and $10,000 respectively, and won't dispute the auditor general's findings before the Senate's newly appointed arbiter.