There were conflicting accounts, however, about whether Isabelle Lapointe is still working for Conservative Senator Pierre-Hugues Boisvenu.
A message left at Boisvenu's office wasn't immediately returned.
Senate Liberal Leader James Cowan said he was disturbed by reports of Boisvenu's relationship with Lapointe and that he's asked the internal economy committee to look into the matter. Cowan said he's been told the committee will interview Boisvenu.
"I do agree that it is entirely improper," Cowan said. "I think any organization that I've been involved in, it would not be proper or appropriate for such a relationship to exist."
Cowan said he wasn't familiar with the rules, however.
"I've not had occasion to look at the Senate rules myself," he said.
Senators give conflicting reports
Conservative Senator Claude Carignan said that Lapointe still works for Boisvenu but that the romantic relationship has ended.
"For the moment she's in the same office," he told reporters outside the Senate chamber.
Carignan also called it a personal matter and said it isn't the Senate's role to enter into people's private lives.
He pointed out the rules say that senators can't hire a spouse or family member. They don't explicitly say senators cannot employ their spouses.
"What I understand is that he didn't hire a spouse or a member of his family," Carignan said.
"Senator Boisvenu has told us that the relationship is over. When he hired her, she wasn't his spouse."
But Conservative Senator Jean-Guy Dagenais contradicted Carignan.
"We know that Mme. Lapointe no longer works for Senator Boisvenu. That's all I can tell you, it's all that I have," Dagenais said, calling it a very personal matter.
Dagenais said his office is across the hall from Boisvenu's and he hasn't seen Lapointe this week.
"They told me she was transferred to another office. I don't have the information [on which office], but she is no longer working for Senator Boisvenu," he said.
Dagenais said he didn't know whether the relationship was over. He said he doesn't believe the news detracts from Boisvenu's work on behalf of victims of crime.
"The relationship was revealed March 2 by a story in the Quebec newspaper La Presse. Boisvenu declined to comment to the newspaper, calling it personal.
Taxpayers not getting clear answers
There are also questions around Boisvenu's expense claims after it was revealed he has been spending most of his time in Gatineau, Que., just outside Ottawa.
NDP ethics critic Charlie Angus said he didn't want to get into Boisvenu's personal life.
"My concern is whether or not he's eligible to accept a housing allowance from the taxpayer while he's going through a divorce, moves out, apparently, from his wife and then continues to claim a housing allowance."
At least three other senators have come under scrutiny for claiming living expenses when they are known to have lived in the Ottawa area for years. Conservatives Patrick Brazeau, Mike Duffy and Pamela Wallin, and Liberal Mac Harb, are all undergoing an outside audit of their expenses.
Another Conservative senator, Dennis Patterson, reportedly lives mostly in Vancouver but represents Nunavut, but the Senate's internal audit found he was properly claiming a living expense.
Angus drew a comparison with Canadians falsely claiming a child as a dependent.
"They'd be charged. They'd be charged with defrauding the taxpayer. So I don't know exactly what's going on with Mr. Boisvenu, but I feel that like Ms. Wallin, Mr. Duffy, Mr. Patrick Brazeau, Mr. Patterson, taxpayers are not getting clear answers and Mr. Boisvenu and the rest of them need to come clean and we need an investigation into what's happening with this broken honour system."
Expenses for Gatineau home
Boisvenu says he has proven that his primary residence is in Sherbrooke, Que., and his secondary residence is in Gatineau.
According to a source, Boisvenu hasn't lived in their Sherbrooke condominium since he and his wife separated in February 2012.
Boisvenu told The Canadian Press that he's in the process of separating from his wife and that the issue should be a private matter.
Senators can claim up to $22,000 a year in living expenses, as long as their primary residence is at least 100 kilometres from Ottawa.
He says he's in compliance with the Senate guidelines.
"I provided all the documents that show that my primary residence is in Sherbrooke and my secondary residence is here [in Gatineau]," he said by phone Sunday.
"When the divorce is made official, I'll have a decision to make."
Boisvenu acknowledged that many of his clothes and belongings were with him in Gatineau, but he said he has regularly returned to Sherbrooke in recent months to meet with a divorce lawyer and stays at the home when he does.
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