TORONTO - A notorious pair of Ontario Conservatives who spent the night couch-surfing in the legislative lounge and snacking on smuggled fruit led a deafening, desk-pounding protest for the second day in a row Tuesday, in an all-out effort to derail tax harmonization.

Speaker Steve Peters took the unusual step of scuttling question period over the ear-splitting din of the Progressive Conservatives, who staged a sit-in over the government's refusal to hold provincewide public consultations on the tax change.

Bill Murdoch and Randy Hillier, who were banished Monday from the chamber, grabbed front-row seats in the legislature Tuesday after sleeping overnight in an adjoining lobby that afforded such small comforts as couches and a bathroom.

Ignoring their assigned seats in the backbenches, the two party mavericks positioned themselves close to Peters, leading their caucus colleagues in an unrelenting campaign to drown out debate by shouting and slamming the lids of their wooden desks.

The conflict escalated as Peters tried to bring the unruly Tories under control by pausing the proceedings several times and refusing to recognize the votes of party members who weren't sitting in their own seats.

That only seemed to egg on the Tories, who accused Peters of being "undemocratic" by not counting their votes.

The battle reached a climax when, despite repeated requests to return to their assigned seats during question period, Murdoch and Hillier refused to budge.

That prompted Peters to walk out, shutting down the only time set aside for the opposition parties to hold the government to account in the legislature.

"I am not prepared to continue with question period while these two members are occupying the front benches," Peters said.

No resolution seemed to be in sight Tuesday despite several closed-door meetings with representatives from all three parties.

Premier Dalton McGuinty shrugged off the protest and refused to get involved.

"Until the day that we said we were going to move ahead with the HST, they were in favour of it," he said.

"The federal Conservatives support this. The federal Liberals support this. There is an NDP province in Canada where the HST is in place. In an odd kind of way ... this is almost a non-partisan issue."

The Tories insist they won't give up until they get at least one day of public hearings outside Toronto on the harmonized tax legislation, while the governing Liberals derided the antics as nothing more than playing to the cameras.

The two Conservatives can be removed by force, but Peters said he was loath to take the unprecedented step of dragging out two elected politicians.

The clearly uncomfortable Speaker said he allowed Murdoch and Hillier to sleep in the adjoining lobby to avoid a repeat of what happened in 1995, when Liberal Alvin Curling staged an overnight sit-in to protest a Conservative government bill, without the benefit of a washroom.

"I did not want to see issues in the chamber of somebody utilizing a bottle to deal with bodily, human functions," Peters said.

If the two politicians leave the main chamber, security guards could bar them from returning until a new legislative session starts with a speech from the throne. That could deprive the 25-member Tory caucus of two votes for months, perhaps even until after the next election in 2011.

Murdoch, who wore a kilt in preparation for the protest, and Hillier have been drinking very little water to avoid any embarrassing incidents, said Opposition house leader Bob Runciman.

But the disruption isn't slowing down debate, which means the Tories are wasting time while government legislation aimed at merging the eight per cent provincial sales tax and the five per cent federal GST continues to wind its way through the legislature, said government house leader Monique Smith.

The Tories shot themselves in the foot again by tanking question period, which has alienated the NDP, their only potential allies in the HST battle, Smith said.

"They need to grow the hell up," fumed NDP Leader Andrea Horwath, whose party has played a key role in trying to break the impasse.

Smith said she offered Monday night to extend public hearings in Toronto from one day to 2 1/2 days, but the Tories never responded.

"Unfortunately, we have an Opposition that's intransigent and we have an Opposition leader who's unable to control at least two of his members," she said.

"And by the actions in question period today, it might be even more than that."

Government sources claim the Tories considered the offer, but Murdoch and Hillier -- who are both notoriously difficult to control -- vetoed it.

Runciman denied that Hillier and Murdoch have gone rogue.

"We're very supportive of Bill and Randy and I think that once this thing is dealt with, I think that it's not going to be a problem," he said.

"They're not going to present a problem for the Speaker, they're not going to present a problem for us. We remain fully supportive of what they're doing."

Other sources close to the all-party talks said the Tories, who have little leverage already, are sabotaging their protest by refusing to yield to even the smallest of demands.

Peters made it clear before question period that if Hillier and Murdoch didn't move to their assigned seats, he would cut off the debate, one source said. The Tories refused, knowing what would happen.

"They don't have an exit strategy," the source said.

The noisy protest petered out in the afternoon, as votes proceeded with little disruption from the Tories.

The Ontario government said it plans to pass the HST bill by Dec. 10, and is prepared for late-night sittings and other measures to ensure it gets its agenda accomplished by the holiday break.

"I'm going to be in question period tomorrow," McGuinty said. "I hope there are going to be questions asked. I hope we're going to have a question period tomorrow."

Like Ontario, British Columbia will also harmonize its PST with the GST on July 1, something Quebec, New Brunswick, Nova Scotia and Newfoundland and Labrador have already done.