OTTAWA -- Opposition parties, and even some Tories, are urging the Speaker to stem the tide of partisan vitriol in the House of Commons before it becomes an all-party war of mutual rhetorical annihilation.

They want Andrew Scheer to clamp down on the trash talk that's turning members' statements -- the 15-minute interval preceding question period each day -- into little more than a series of nasty partisan attack ads.

Members' statements are intended to give MPs a chance to address the Commons for up to one minute on any matter they choose -- tributes to deceased constituents, events in their ridings, causes dear to their hearts.

Partisan shots have always been part of the mix but for the past few years the Conservatives have been systematic in using member's statements to orchestrate repeated, scripted verbal broadsides against the leader of the Opposition. They did it to Liberal leaders Stephane Dion and Michael Ignatieff, despite repeated rebukes by former Speaker Peter Milliken, and now they're doing it to NDP Leader Tom Mulcair.

But the NDP is now starting to respond in kind and Nathan Cullen, the party's House leader, is worried the partisan sniping will only escalate if Scheer doesn't put a stop to it.

"The problem is that when you see it day after day after day, there's a tendency to want to retaliate and bring the tone of debate even lower than it is now," Cullen said in an interview.

Cullen has told Scheer the NDP would fully support him were he to cut off MPs who abuse members' statements and he intends to speak to him again this week to say, "I think this is getting worse, not better."

"If the Speaker doesn't clamp down then it's hard for me to hold off my attack dogs because they say, 'They're punching our party or leader in the nose every day, we need to respond."'

Interim Liberal leader Bob Rae is also urging Scheer to step in.

"He could rule them out of order, very simply," Rae said last week.

"(Members' statements) were not intended to be partisan rants that are written by 25-year-old enthusiasts in the Prime Minister's Office."

Even some Tories want Scheer to put an end to partisan attacks during members' statements. Cullen said some Tory backbenchers have privately told him they're embarrassed by the sophomoric scripts and have refused to read them.

In a fascinating blog post last week, a former senior adviser to Prime Minister Stephen Harper described how the tactic was initially to use only the last statement before question period to attack and destabilize the Opposition leader just as he was about to rise to ask the first question of the day. Keith Beardsley bemoaned that it's now become "standard practice" for most members' statements.

"In my opinion, this has been one of the contributing factors to the caustic atmosphere you now see on a daily basis in the House of Commons."

Beardsley said the Speaker should formulate strict, new guidelines for members' statements or "do away with them altogether."

Heather Bradley, spokeswoman for Scheer, said the Speaker "is mindful of the importance of ensuring exchanges in the House are civil and courteous.

"At the same time, all members enjoy freedom of speech, which the Speaker must protect and, unless statements are clearly and undoubtedly out of order or are creating disorder, the Speaker does not intervene."

Bradley added that Scheer is guided by previous rulings by Milliken and listens carefully to statements "to ensure they do not veer into blatant personal attacks."

Milliken vetoed personal attacks during members' statements, noting that the targets have no opportunity to respond, unlike question period or debates in the Commons. He occasionally cut off MPs mid-statement and went so far as to warn one Tory backbencher he'd be suspended from the Commons if he continued using his statements to launch personal attacks on Ignatieff.

The Tories adapted their approach to avoid Milliken's wrath. They took to issuing scathing assessments of an unidentified politician, whom they would identify as Ignatieff only at the very end of their statements -- when it was too late for Milliken to cut them off.

More recently, the Tories appear to have finetuned the tactic to avoid anything that Scheer could deem a direct personal attack.

Since Parliament resumed two weeks ago, two to four Tory backbenchers each day have used members' statements to hammer away at Mulcair's alleged plot to impose a "reckless," "sneaky" "job-killing" carbon tax that would "raise the price of everything, including gas, groceries and electricity" -- regardless of the fact that Mulcair has actually proposed a cap and trade system similar to that proposed by the Conservatives themselves in 2008.

The statements have focused on the alleged policy, rather than on Mulcair personally, making it harder for Scheer to find grounds to rule them out of order.

And so the NDP has begun to strike back with its own attack statements.

"Conservatives care more about making up a tax on the Opposition than acting on Canadians' priorities," Toronto New Democrat Dan Harris said in one such retaliatory statement.

"Perhaps the next Conservative speaker will throw away his anti-NDP rant and instead tell Canadians exactly what their government is planning to do about rising gas prices."

Cullen said the NDP is allowing itself one statement a day to be "a little more forceful" and is trying to inject a bit of humour into them so as not to be as "spiteful" as the Tories.

However, last Friday, New Democrat MP Jinny Sims appeared to link anti-abortion Tory MPs to white supremacists in a particularly incendiary statement.

"We're not pure on this either," Cullen allowed.

"It's hard if you just don't see anything changes, if all you're getting is slammed constantly. I see the emails, people urging us to fight back, fight fire with fire, and we resist most of those calls. Yeah, decorum, it's easier to say than to do."