The grand taboo: Do senators meet the constitutional residency requirement?

If there's one subject the government hasn't wanted to touch with a ten-foot-pole, it's the constitutional requirements for a senator's residency.

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The legal criteria a senator must meet in order to represent a particular province is a matter apparently so taboo that a legal opinion a key Senate committee sought on the subject back in 2013 seems to have disappeared into thin air.

That phantom opinion was commissioned at the height of the Senate expenses scandal, before senators Mike Duffy, Patrick Brazeau, Mac Harb and Pamela Wallin were ultimately suspended from the upper chamber.

Now the Senate is also trying to block the release to Duffy's trial of an internal audit it conducted for that same internal economy committee in 2013 to determine whether senators met certain criteria for claiming expenses in the provinces they represent, including having a driver's license and health card in that province.

NDP want report released

'"Will the Prime Minister stand up and demand that his Conservative senators who are his caucus colleagues make this report public?" NDP Leader Tom Mulcair said in question period Tuesday.

"The Opposition leader knows very well that's a matter for the other chamber. It's not a matter for this House or for the government," Stephen Harper responded.

It's important here to separate out two issues constitutional residency requirements and declaring residency for the purposes of claiming expenses.

Duffy is partly on trial for the latter. He triggered $90,000 in living expenses when he signed a declaration saying his primary residence was in Prince Edward Island, and his secondary residency in the Ottawa area, where he had lived for decades.

Whether he is constitutionally eligible to sit in the Senate is a whole other ball of wax.

The Constitution says that a senator must own $4,000 worth of property in the province he or she represents, and must also be "resident in" that province.

What exactly does that mean?

Does Duffy meet that definition, given that he lived most of the time in Ottawa, as he had for decades before his 2008 appointment?

Signed declaration sole requirement?

According to then-government Senate leader Marjory LeBreton in 2013, the mystery legal opinion (apparently never seen by the Liberals on the committee), said all that was required was for a senator to declare they were resident in the province.

"Senators sign a declaration of qualification," LeBreton told reporters at the time.

"That's the document that secures your legitimacy to sit in the Senate. That's aside, so now we're dealing with expenses."

But the Constitution also says that only the Senate has the power to consider challenges to senators' eligibility to sit in the Senate.

That didn't stop the Prime Minister's Office from trying to kill off the conversation on that subject, going so far as meddling in the internal economy committee's report on Duffy's expenses and trying to suss out the direction that an independent audit was taking.

Harper's chief of staff at the time, Nigel Wright, was upset in the spring of 2013 that LeBreton had been part of a bipartisan move to establish criteria for primary residency for expense purposes, blurring the lines with the constitutional issue.

Staff sought to reassure Harper on that front.

PMO sought to 'bring an end' to residency concerns in 2013

"Your office working with Senate leadership to seek to bring an end to concerns regarding the constitutional residency of some of our Senators," Wright and two others wrote to Harper in a February 2013 memo filed in court by police.

As the scandal around Duffy swirled, Harper's office moved into high gear to cut off oxygen from the constitutional residency issue.

LeBreton was given marching orders from the unelected staff.

"I will advise Sen. LeBreton that we will not take any steps in the Senate to address residency for constitutional purposes unless anyone challenges the qualification of any of our Senators, in which case we will defend (and defeat) any motion regarding any Senator who owns property in the correct province and division," Wright wrote in February 2013.

Wright told Mike Duffy a few days later that "we will defend his constitutional residency qualification categorically."

In the House of Commons, Harper did just that.

Government wanted residency issue closed

"All senators conform to the residency requirements," Harper told the House of Commons in late February 2013.

"That is the basis on which they are appointed to the Senate and those requirements have been clear for 150 years."

Wright and his staff also didn't want the external auditors looking into Duffy's expenses to draw a conclusion on his residency.

They coached the Conservatives who controlled the internal economy committee to remove any hard language on Duffy from their final report on his expenses.

They wanted the residency matter closed, but two years later, it is still on the political front burner.

Crown Prosecutor Mark Holmes has said he doesn't think Duffy was constitutionally eligible to represent P.E.I.

And the court has heard that although Duffy was very clearly living in Ottawa at the time of his appointment, neither the Senate administration or the Prime Minister's Office seemed to bat an eyelash.