OTTAWA - Peter Milliken brought the House down Friday, literally and figuratively.

It was an historic ruling by the Speaker of the House of Commons that provided the fodder for the confidence motion that toppled Stephen Harper's minority government.

But just prior to the confidence vote, in the last gasp of the dying 40th Parliament, MPs from all parties set aside their pre-election vitriol long enough to pay tribute to Milliken, the country's longest-serving Speaker.

After 23 years as the Liberal MP for Kingston and the Islands, 10 of them as referee in the Commons, Milliken is retiring from the political arena.

He won a prolonged ovation and effusive praise from all sides -- even the Conservatives, who did not appear to hold Milliken's role in bringing down the government against him.

"For four terms as Speaker, you have conducted yourself with great integrity, with great professionalism," said John Baird, the government House leader.

"You're thoughtful, you're intelligent and, Mr. Speaker, you have enjoyed the confidence of this House each and every day, during every sitting day of those four (terms) and that is a remarkable accomplishment."

Baird concluded that Milliken "will go down in history as, if not one of the best Speakers, the best Speaker that the House of Commons has ever had."

Baird's unstinting praise was all the more surprising given that Milliken has thrice in the past year issued unprecedented rebukes to the government for disrespecting the rights of MPs and the traditions of parliamentary democracy.

Last year, Milliken ruled the government had breached parliamentary privilege by refusing to disclose sensitive Afghanistan detainee documents. He said Parliament has an absolute and unlimited right to see information, even if it involves national security.

That ruling forced the government to strike a deal with two of three opposition parties for vetting, and eventually releasing, the documents. None have been disclosed thus far.

Earlier this month, Milliken similarly rebuked the government for refusing to fully disclose the cost of its tough-on-crime-agenda, corporate tax cuts and plans to purchase stealth fighter jets. That ruling formed the basis for Friday's confidence motion declaring the government in contempt of Parliament.

Milliken also ruled that International Co-operation Minister Bev Oda breached parliamentary privilege by misleading Parliament about an altered government document. Friday's dissolution allowed Oda to dodge a formal contempt citation.

All three opposition parties praised Milliken for asserting the rights of Parliament.

Liberal Leader Michael Ignatieff said Parliament is losing "a fierce protector of its privileges."

"Few Canadians have done more to affirm the supremacy of Parliament. Three times in the last year, you have stood in this House to defend our democracy against the abuse of power."

Pierre Paquette, the Bloc Quebecois House leader, said Milliken ensured "balance was maintained here, between the Parliament and the prerogatives of the government, which is not always an easy thing to do."

Libby Davies, the NDP House leader, said Milliken will be remembered for his fairness, impartiality, good humour and depth of knowledge about arcane parliamentary procedure.

"You know this place inside-out and all of its strange practices that no one really understands but that at certain moments become important, or even critical, to how we function and how we do our work for Canadians," she said.

Milliken is a lifelong student of parliamentary procedure. He began reading Hansard, the official record of parliamentary proceedings, when he was a teen.

Saying goodbye to it all on Friday was clearly difficult.

"When you elected me to this job, you raised me high in this House," he told the Commons, his voice breaking with emotion.

"But what has been the wonderful part about it is the affection and respect that you've showered upon me since my first election."

Milliken was elected Speaker four times. Of the 10 tie-breaking votes cast by Speakers in Canadian parliamentary history, Milliken cast five of them.

Indeed, it was his vote that staved off defeat of Paul Martin's minority Liberal government in 2005 -- the only time a Speaker has been called upon to determine the outcome of a confidence vote in Canada.

His last act as Speaker was to announce Friday that the Liberal motion of non-confidence in the Harper government had been adopted.