Wallin, along with Senators Mike Duffy and Patrick Brazeau, face motions that would suspend them from the Senate, and strip them of pay and benefits because of inappropriately claimed expenses.
The motions will be voted on Wednesday if they aren't sent to committee for study, as Liberal Senate Leader James Cowan proposed Tuesday.
If Wallin rises in her own defence, her speech would follow the explosive tirade Duffy let loose Tuesday as he aimed accusations not just at the Prime Minister's Office and some former Senate colleagues, but at Stephen Harper himself.
Wallin, like Duffy, is a former TV host and compelling speaker who used to be paid handsomely to speak in public, so her address, if it happens, could be as dramatic and jaw-dropping as Duffy's.
Duffy, in a riveting speech, detailed conversations he claimed he had with Harper and PMO officials, as well as the Conservative Senate leader at the time, Marjory LeBreton, about a deal he said he had struck with them to contritely pay back his expenses.
If he didn't comply, Duffy charged, he was threatened with expulsion from the Senate and the loss of his paycheque.
Wallin did not get a chance to speak Wednesday in the Senate before time ran out and the sitting was adjourned.
Brazeau did address the Senate about his case, saying, "If this is the Harper government's way of believing in democracy, we should all be very fearful. This is a complete joke, a farce."
Brazeau also gave notice of a motion of his own, asking to meet with the Senate internal economy committee in public, rather than behind closed doors as this committee usually operates, and discuss his housing claims. His motion might be debated Wednesday.
Spotlight on travel expenses
Wallin, like Brazeau and Duffy, was audited by the private accounting firm Deloitte. That report identified a pattern of Wallin flying to Toronto frequently, but using her Senate travel points meant to apply to trips between Ottawa and Saskatchewan, the area she represents in the Senate.
The Senate's internal economy committee voted to forward her report to the RCMP, but did not give Wallin an opportunity to defend herself before committee members. The committee also did not formally adopt the report, as it did in similar reports done on Duffy and Brazeau.
Wallin has already repaid approximately $140,000 in expenses, saying she made honest mistakes, although she called the Deloitte report "flawed and unfair."
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