Denise Batters, a Regina lawyer and senior figure in the province's Crown Investments Corp., is the widow of Conservative MP Dave Batters, whose suicide prompted Harper to deliver an emotional call to arms at his funeral.
"We know this much," the prime minister said. "Depression can strike the sturdiest of souls. It cares not how much you have achieved, nor how much you have to live for."
In a brief interview Friday, the newly appointed Batters — since becoming a prominent advocate for mental health — said she plans to keep up the fight to raise public awareness about depression once in Ottawa.
"That will remain a personal priority of mine, definitely," Batters said, describing as "amazing" the opportunity she will now have to walk the same corridors of power as her husband once did.
The Prime Minister's Office said the new senators are committed to reforming the upper chamber, and have also expressed support for term limits and efforts to push provinces and territories to hold Senate elections.
Currently, that only happens in Alberta, where last year's winner Doug Black landed in hot water as a result of his expenses as president of the University of Calgary's board of directors.
Black eventually stepped down from the role, but not before repaying nearly $5,400 in airfare expenses the university said were "processed in error." The Canadian Taxpayers Federation also raised questions about his hotel bills.
Black also has a close connection to disgraced senior Conservative aide Bruce Carson. The pair worked together at the Energy Policy Institute of Canada, a lobby group and think tank set up by the energy sector.
A slew of senators are currently under investigation for their own expense claims, including how they spend their housing allowances.
In addition to the vacancies in Alberta and Saskatchewan, Harper filled two empty seats from Ontario and one from Newfoundland and Labrador.
To fill the Ontario seats, Harper named Lynn Beyak, a small-business owner from the province's northwest, and Victor Oh of Mississauga, president of a property development firm.
Beyak has been a community activist and is a former chair of the Fort Frances-Rainy River board of education and a former member of the board of the province's Trillium Foundation.
Oh is the funding chairman of the Canada-China Business Communication Council and a member of the board of governors of Sheridan College.
He was also heavily involved in Harper's first trip to China in 2009, a visit that was widely seen as a turning point in Canada-China relations.
David Wells, until recently the deputy chief executive of the Canada-Newfoundland and Labrador Offshore Petroleum Board, takes the final seat.
Wells is a businessman who has also held senior positions in the federal Fisheries Department. He has been a Canadian delegate to the Northwest Atlantic Fisheries Organization.
The new senators are "remarkable Canadians who have distinguished themselves in their respective pursuits," Harper said in a release.
"I look forward to working with these talented individuals in Parliament. Their collective experience and dedication are most welcome."
The Conservatives now hold 65 of the 105 available Senate seats. The rest include 36 Liberals, one Progressive Conservative, two independents and one vacancy.
A bill to reform the Senate was introduced by the Tories in 2011, but has languished in the House of Commons.
The Opposition New Democrats were quick to remind Harper of his prior commitment to reform when he was Opposition leader. They said Canadians deserve better than seeing another five people get a "golden handshake."
Senators collect a salary of about $132,000 a year, plus various allowances, as well as a pension.
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