The ongoing Senate expense scandal unfolding in Ottawa has a New Brunswick connection as embattled senators Pamela Wallin and Mike Duffy each raise questions about New Brunswick Senator Carolyn Stewart Olsen.

Saskatchewan Senator Pamela Wallin defended herself Wednesday in a lengthy speech that included questions about why Stewart Olsen isn't also in hot water.   

"For example, one of the senators who sits in judgment of all of us, who had her sights trained on me from the beginning, Senator Stewart-Olsen, has recently had questions raised about her own probity in relation to her residential expense claims," Wallin said in the Senate.  

Stewart-Olsen has been a New Brunswick senator for more than four years. Originally from New Brunswick, she was a long-time resident of Ottawa when first appointed. She now lives in Cape Spear.

Questions about Stewart-Olsen centre on how quickly she moved following her Senate appointment — and whether some New Brunswick residency expense claims were filed when she still lived in Ottawa.

Close relationship with Harper

Stewart-Olsen is former aide to Prime Minister Stephen Harper who, until this week, was a key member of the Senate committee that sat in judgment on Wallin and three other senators, ordering external audits of their expenses and ultimately asking the RCMP to investigate all four.

During one attempt by reporters to get Harper to answer questions on the Senate scandal at a Conservative caucus meeting last summer, she alone got out of her seat and blocked cameras from getting any more pictures. Wallin said that relationship is why Stewart Olsen is not in trouble.

'They resented me being an activist senator.'- Pamela Wallin on Marjory LeBreton and Carolyn Stewart Olsen

"But of course there will be no Deloitte audit in her case," she said. "Apparently, the Committee on Internal Economy, of which she has long been a member, intends to consider her matter in private. This is a double standard — she gets kid-glove treatment and I'm unfairly singled out for a retroactive audit."

Wallin said public opinion was whipped up against her by 14 different leaks to the media — leaks she believes were orchestrated in large measure by senators Marjory LeBreton and Stewart Olsen and which were designed to cast her conduct "in the worst possible light."

The pair "could not abide the fact that I was outspoken in caucus, or critical of their leadership or that my level of activity brought me into the public eye and once garnered the praise of the prime minister," Wallin said, her voice occasionally wavering.

"They resented that. They resented me being an activist senator."

LeBreton rose immediately following Wallin's speech to call her accusation "false, false, false."

LeBreton denied ever leaking information about Wallin to the media or instigating the investigation into her expenses. Indeed, LeBreton said it was a letter of complaint to Senate administration from one of Wallin's own staffers that prompted a review of her travel claims.

Meanwhile, Stewart Olsen has consistently denied there are any residency expense issues attached to her appointment as a New Brunswick Senator. 

Duffy says Stewart Olsen part of PMO ultimatum

It wasn't only Wallin targeting her.

On Tuesday, Duffy implicated Stewart Olsen in the ultimatum he says he was given by the Prime Minister's Office — that if he didn't pay back his disallowed $90,000 in expenses, she and fellow committee member Sen. David Tkachuk would declare him unqualified to sit in the Senate.

Stewart Olsen and Tkachuk have also been accused of whitewashing the initial committee report on Duffy to essentially exonerate him of any deliberate wrongdoing.

Both have denied the accusations. 

Harper's chief of staff, Nigel Wright, resigned in May after news leaked that he had personally given Duffy a $90,000 cheque to reimburse the Senate.

LeBreton resigned as government leader in the Senate over the summer.

LeBreton, Wright, Tkachuk and Stewart Olsen were all fingered by Duffy on Tuesday as being part of a "monstrous" conspiracy to pressure and intimidate him into accepting Wright's deal, even though he didn't believe he'd done anything wrong.

With files from The Canadian Press