If he doesn't pay up, according to a terse statement issued May 14 by the government leader in the Senate, Marjory LeBreton, "The Senate will seize the funds."
A Senate communications spokeswoman, Annie Joanette, said in an email Thursday that "should it happen that a deadline for repayment were missed, the issue would then be addressed by the [Senate] committee and an appropriate response decided."
Expense claims made by Brazeau, along with two other senators, Mike Duffy and Mac Harb, are being investigated by the RCMP.
A spokeswoman for Brazeau's office, Debby Simms, said in an email Thursday that "we can confirm that we spoke with them [the RCMP]. We are unable to provide any details other than to say that it is only through objective, apolitical eyes will the facts ever become known to Canadians."
Simms also said Brazeau is "reaching out" to the auditor general and the Senate ethics officer, as well as to experts in government accountability and contract law, about the Senate's "questionable actions" toward him.
Simms did not directly address a question about whether Brazeau intends to repay the money, but on May 16 Brazeau told Evan Solomon of CBC News Network's Power & Politics, "Until I get clear answers to my questions, the answer is no."
Brazeau wants a public inquiry
Brazeau said he wants the Senate to explain its rules about how primary residence is determined. He has also said he'd like to see a public inquiry into the matter.
Brazeau, appointed by Prime Minister Stephen Harper in 2009 as a senator representing Quebec, claimed his primary residence is in Maniwaki, Que., 135 kilometres from Ottawa. Senators are permitted to claim living expenses in Ottawa if they live 100 kilometres or more from the capital. Brazeau claimed money for renting a townhouse in Gatineau, Que., just across the river from Ottawa, calling it his secondary residence.
However an audit by the private accounting firm Deloitte revealed that during an 18-month sample period from April 2011 to September 2012 Brazeau spent only 10 per cent of his time in Maniwaki. Despite this finding, Deloitte found that Senate rules are unclear about criteria establishing primary residency.
Deloitte also found that Brazeau’s health card, driver’s licence, provincial income tax form and voting record showed his address as Maniwaki.
"Nowhere does it state a senator has to spend five, 10, 15 or 50 per cent of their time in their primary residence," Brazeau told Solomon.
A Senate committee ruled that the small amount of time Brazeau spent in Maniwaki was "contrary to the meaning of the word 'primary,'" and on May 28 gave him 30 days to repay $48,000.
Harb was also ordered to repay $51,000 because he claimed his primary residence is in a house just over 100 kilometres from Ottawa, although he was a resident of Ottawa for decades before being appointed to the Senate. His deadline for repayment comes up next week. Harb has filed an application for judicial review in the Ontario Superior Court over the Senate order.
The Senate also found Duffy inappropriately claimed $90,000 in expenses, but he repaid the money using funds given to him by Harper's former top aide, Nigel Wright.
Unlike the other two senators who claimed $88 per day for meals when on Senate business, which the Senate says they must repay, Brazeau never claimed per diems during the Deloitte examination period.
Brazeau, whose correspondence says he is an Independent Algonquin senator, was expelled from the Conservative caucus and suspended from the Senate in February over a completely separate criminal charge currently before the courts, although he still collects his Senate salary.
Also on HuffPost