House of Commons Speaker Peter Milliken has been cutting off MPs who use private members' statements to attack other MPs. (Sean Kilpatrick/Canadian Press)

The House of Commons referee has begun enforcing a rule aimed at improving parliamentary behaviour, a move that has displeased the governing Conservatives.

Speaker Peter Milliken cut off Tory MPs three times Thursday as they began taking shots at Liberal Leader Michael Ignatieff during member statements.

Milliken had already warned members that he was fed up with the proliferation of personal attacks in their statements ahead of the daily question period.

While all parties take pot-shots occasionally, the Conservatives have long been systematically attacking the Liberal leader in their statements.

Milliken told members that the Commons rules preclude using the statements to attack opponents.

He cited the 1983 introduction of members' statements, at which point Speaker Jeanne Sauvé declared that personal attacks, frivolous matters, poetry recitals, and congratulations were forbidden.

Members have usually used their one-minute speech time to salute distinguished Canadians who have died, speak on policy matters, or congratulate local athletes on a championship.

Milliken said he might turn a blind eye to the congratulations but wants the attacks toned down.

"It represents a shift," he said of his decision. "I have made the shift because of complaints from all sides of the House about the lack of decorum — particularly in that [statements] part."

Milliken, a Liberal MP, has been elected seven times by his peers to serve as the Commons Speaker and was applauded for his fairness when most recently elected last fall.

MPs from three parties gave Milliken an ovation Thursday. But the Conservatives were angry.

Conservative MP Pierre Poilievre says the Speaker's ruling is an attempt to stifle debate in the House of Commons. (Sean Kilpatrick/Canadian Press)

Ottawa-area Tory Pierre Poilievre vigorously defended the right to criticize. He suggested the Speaker might have succumbed to pressure from fellow Liberals.

"Part of a democracy is promoting ideas. The other part of a democracy is pointing out the flaws in some of those ideas," Poilievre said.

He added it should be up to voters to scrutinize and judge MPs for their behaviour in the Commons, not the Speaker.

Milliken rejected the suggestion he was stifling debate. He said there are plenty of opportunities throughout the day to debate ideas, when opponents can respond.

The format of members' statements does not allow for a response.

On Thursday, Conservatives used their statements to criticize Ignatieff's writings about Russia and Ukraine, and accused him of planning to bring back the Liberal carbon tax plan, of seeking to scrap parental benefits, of having a hidden agenda, of wanting to prevent Canada's economy from recovering, and of getting his economic advice from adviser Warren Kinsella.

Milliken cut them short three times.

The NDP, Liberals and Bloc Quebecois saluted his decision.

"It doesn't even go far enough," said New Democrat MP Yvon Godin.

"We receive letters from students and schools and teachers who tell us they don't want to bring their students here in the House of Commons because of the lack of respect we see here."

The Tories countered that the opposition has used members' statements in the past to attack them —and that Milliken let it slide.

The Conservatives pointed to statements from the Liberals in 2005, to one statement in 2008, and to a week in mid-2006 when the Liberals attacked them every day.