The growing call for a full federal inquiry into missing and murdered aboriginal women got an unexpected boost after the New Democrats took advantage of the typically sparse end-of-week turnout in the House to seize control of the parliamentary agenda.

The party was able to force the chamber to hold an impromptu debate on the report from the special House committee that looked into the issue earlier this year.

The Conservative-controlled committee ultimately chose not to recommend a full inquiry, but both the New Democrats and the Liberals submitted minority reports in support of a national public commission of inquiry.

New Democrat MP Romeo Saganash led off the debate with an emotional — and deeply personal — plea for a federal investigation.

Saganash told the Commons about his own family's painful experience of not knowing what happened to his missing brother until they were finally able to see where he was buried, decades later. He said learning the truth offered his family closure, and that's what the families of missing women need too.

The NDP has promised to hold an inquiry should it form government after the next election. So far, the Conservative government has not been willing to call an inquiry. However, it is open to a compromise proposal originating from the provincial premiers meeting last month to create a national roundtable to tackle the issue.

After just over an hour, the debate was suspended to allow the House to move on to private members' business. The remaining time must be scheduled within the next 10 sitting days, after which MPs will be able to vote on whether to adopt the report.

Tactics in the House

So, how exactly did the New Democrats manage to manoeuvre the Commons into hosting an impromptu hour-long debate on their chosen topic?

As is ultimately always the case in the House of Commons, it came down to the numbers — and specifically, an NDP gamble that the government simply wouldn't be able to muster a sufficient contingent of Conservative MPs to override the combined opposition forces in a rare Friday vote.

Shortly after question period wrapped up, New Democrat MP Yvon Godin segued from introduction of a private member's bill to propose that the House move to the next stage of routine proceedings — in this case, first reading of Senate public bills.

It was an ironic choice for a party long opposed to the very existence of the Upper House — but an effective one, strategically, as it could have served as a test to see just how many Conservative MPs the government could get to the House on short notice.

The answer: not enough, which is why the Conservatives ended up voting in favour of the NDP motion, and didn't take the usual steps to shut down the concurrence debate before the allotted time ran out.

The government's decision to back down from a vote that would almost certainly have resulted in an unprecedented defeat on the Commons floor didn't deter New Democrats from publicly celebrating their victory.

'Asleep at the switch'

NDP Leader Tom Mulcair, who is currently on tour in New Brunswick, took to Twitter to proclaim that he was "beaming with pride."

Beaming with pride. Today, the <a href="https://twitter.com/hashtag/NDP?src=hash">#NDP</a> took control of the House of Commons & triggered a debate on a public inquiry on <a href="https://twitter.com/hashtag/MMIW?src=hash">#MMIW</a> <a href="https://twitter.com/hashtag/cdnpoli?src=hash">#cdnpoli</a> —@ThomasMulcair

British Columbia MP Jinny Sims tweeted that it was "such a privilege to be in the House — proud of caucus."

<a href="https://twitter.com/hashtag/NDP?src=hash">#NDP</a> forces debate on murdered, missing aboriginal women. Such a privilege to be in the House. Proud of caucus —@jinnysims

The party also sent out an email to supporters under NDP whip Nycole Turmel's name.

"You're probably not watching House of Commons proceedings this Friday afternoon, so I wanted to fill you in on what just happened," the note began.

"Moments ago, we caught the Conservative government asleep at the switch. When they didn’t show up for work today, our NDP team won a vote to take control of the House agenda."

Notably, the email didn't include a pitch for donations.

Instead, it invited supporters to sign the party's petition calling for a national inquiry into missing and murdered indigenous women.

For their part, the Conservatives downplayed the significance of the move, and pointed out that the party didn't actually have to force the vote to trigger debate on the vote.

"As you know, the NDP can move concurrence any time during Routine Proceedings," Government House Leader Peter Van Loan told CBC News in a written statement.

"The NDP could have moved this motion on Monday, Tuesday or yesterday — but did not."

The government "had no reason to block debate," he said, and both Environment Minister Leona Aglukkaq and Status of Women parliamentary secretary Susan Truppe "actively participated" in the discussion.