But he also chided the NDP for waiting more than a month to lodge a formal complaint.
In a decision handed down on Thursday, Scheer sided with New Democrat House Leader Peter Julian, who had argued that Standing Order 56.1, a little-known House provision that requires 25 members to block a minister's request for unanimous consent, was never intended to be used to issue instructions to committee.
"The House does have the power to give instructions to committees but it is how this is achieved that is important," Scheer said.
"The Chair does not believe the House ever intended that this be done by way of Standing Order 56.1."
He also dismissed Government House Leader Peter Van Loan's contention that the motion in question was "routine."
"The Government House Leader may have been correct in noting that substantive motions are used in the passage of legislation but one cannot draw the conclusion from that that, therefore, motions not related to legislation are routine," he pointed out.
No objection to motion at the time: Scheer
In fact, Scheer advised the House, he very likely would have ruled the motion out of order at the time — had he been asked to do so, that is, which he was not.
"In the absence of any objection at the time that the motion was moved, the matter went forward and the motion was adopted," Scheer noted.
Julian waited so long to raise his point of order, in fact, that by the time he did so, the terms of the motion — namely, instructing the committee to launch its investigation into NDP spending and hear from Mulcair — had already been carried out, leaving the Speaker with little recourse and no obvious remedy.
"As the history of the use of motions under 56.1 demonstrates, past Speakers have all struggled with this dilemma and have almost invariably allowed even motions about which they had reservations to go forward, having had no time to properly assess their content and formulation," Scheer said.
"This is done in the expectation that alert Members of the opposition will, if they deem it appropriate, rise to object."
In this case, he noted, no one did.
Ruling could bolster NDP call to end probe
Scheer also expressed concern over what he sees as the "continuing trend away from the original intent" of that particular parliamentary rule.
To that end, he said it might be "helpful" for the procedure and house affairs committee to study the matter and, ideally, "define the spirit and limitations" of SO 56.1
That is, of course, the very same committee that the House ordered to look into NDP spending practices in the first place.
It's not clear what, if any, effect Scheer's decision could have on that investigation.
Last week, Conservative and Liberal committee members teamed up to adopt a motion inviting House of Commons Clerk Audrey O'Brien to appear at a future meeting in order to respond to the NDP's repeated assertion that House administration was fully aware that it was footing the bill to staff those satellite offices in Quebec and Toronto.
O'Brien is currently on medical leave, but is expected to be back on the job by mid-July.
But Scheer's conclusions could bolster the party's efforts to convince committee chair Joe Preston to bring down the gavel on further hearings, on the grounds that the original House order should never have been allowed to proceed.
At the very least, the retroactive ruling will likely protect Mulcair from any further attempt by committee members to compel him to return for a second round of questions.
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