Just when Stephen Harper was getting a reprieve from daily questions about Senator Mike Duffy's case, a new media report that Senator Pamela Wallin's file has been handed to the Crown is renewing focus on the Senate expenses scandal.

While campaigning at a factory in Burlington, Ont., Harper wasn't asked specifically about the CTV News report about Wallin's case. Instead, he was questioned about whether Wallin's initial repayment of $38,000 of her questionable claims was part of a scheme to derail an audit into her expenses.

The crowd of Conservative supporters booed, as they have at other events where Harper was asked questions about Duffy.

Harper replied, "As I said at the time, I said that all of the individual expenses of all senators would be looked at, and those who were not following the rules would be held accountable. That is exactly what has happened in that and in the case of every single senator."

Harper had defended Wallin's claims

It was a much different response from the one he gave in Feb. 13, 2013. Standing in the House of Commons, Harper defended Wallin's Senate expense claims, saying he had looked at the numbers and that her costs were comparable with any parliamentarian travelling from her area of the country.

With the Duffy trial on hiatus until mid-November, the daily headlines about the involvement of the Prime Minister's Office in that scandal had begun to taper off. Duffy has pleaded not guilty to 31 charges of fraud, breach of trust and bribery related to expenses he claimed as a senator and later repaid with the $90,000 he received from Nigel Wright, Harper's chief of staff at the time.

Wallin's name came up among the emails presented as evidence in the Duffy trial. In one dated Feb. 19, 2013, written by Wright to then government leader in the Senate Marjory LeBreton, the chief of staff says, "I would expect that Sen. Wallin would be given the opportunity to address any unusual expenses through repayment if that is appropriate, as she has done with some inadvertently claimed."

Another email, dated March 8, referred to a question posed by a PostMedia reporter about whether the Conservative Party was going to help repay Wallin's expenses that involved partisan work.

​That led to the now controversial email from Wright to Chris Woodcock, director of issues management at the time.

Wright, under the subject line "Re Sen. Wallin," wrote "FYI only. No discussions with Wallin. There was discussion re Duffy but decided no [Conservative Party of Canada] funds to be used."

Wright then added: "For you only. I am personally covering Duffy's $90K." Woodcock, in court, said he never read that part of the email, and that he never knew about Wright's repayment, prompting more questions on the campaign trail for Harper about who knew what.

So these new developments involving the controversial expenses of another Conservative-appointed senator are obviously unwelcome news to the Tories, particularly if they were to lead to charges against Wallin.

Few details are known about the latest developments in Wallin's case, only that the RCMP, which had been examining 150 expense claims of the senator, have handed over their file to the Crown.

Terrence O'Sullivan, a lawyer for Wallin, told The Canadian Press that neither Wallin nor himself has been told by the Mounties or Crown attorneys that her investigative file is now under review to see if criminal charges should be laid.

In March, new documents revealed that the RCMP had zeroed in on 21 claims with regard to meetings with the University of Guelph, BMO Nesbitt Burns and CTV. Those claims are worth $25,567.31, according to the RCMP's forensic accountant.

Accused of filing expense claims twice

The investigator said he believed Wallin filed her expense claims twice, once with the Senate and again with those companies, and that he believed she committed fraud and breach of trust.

"Senator Wallin, when questioned during an external audit, misrepresented the nature of these trips to Toronto," Cpl. Rudy Exantus wrote in an affidavit.

"I believe that Senator Wallin breached the standard of responsibility and conduct demanded of her and by the nature of her office. I believe that Senator Wallin's conduct represent[s] a serious and marked departure from the standards expected of a Canadian senator."

None of these allegations have been proven in court.

The expense claims were filed between Jan. 15, 2009, shortly after Wallin was named to the Senate, and Sept. 25, 2012.

In an interview with CBC News chief correspondent Peter Mansbridge in 2013, Wallin apologized for mistakes she may have made in some of the filings on her travel claims. She has since paid back a total of $154,191.29.