Parliament Hill is abuzz with speculation this week about a tactic the Opposition Liberals may use to force an election before the government brings down its next budget later this month.

The Liberals are reportedly considering pushing for a no-confidence vote to defeat the Conservative government before the March 22 budget.

Their motion would hinge on House Speaker Peter Milliken issuing a ruling that the Tories were in contempt of Parliament over their refusal to disclose the projected cost of a series of crime bills, as well as controversies such as the Conservative campaign expense case and allegations of misdeeds by Cabinet ministers.

CTV Ottawa Bureau Chief Robert Fife said Tuesday that the Liberals have already decided to defeat the government and send the country into an election campaign, and are now focusing on how exactly to do that.

"They want an election campaign regardless. They've made up their mind last fall, that when the budget time came around they would defeat the government," he told CTV News Channel.

Fife said the Liberals want to avoid voting against a budget that is rumoured to include up to $700 million for low-income seniors, funding for small business and forestry worker job retraining.

"I think they're looking for another trigger to be able to defeat the government, they want something that shows this is an undemocratic government, bad guys," he said. "But I don't think that's realistically going to happen … because the NDP would be unlikely to bring the government down on that: it doesn't fit their narrative."

Any motion to defeat the Conservatives can only succeed if all three opposition parties team up against the government and so far, none of them have given any indication of unanimous agreement to defeat the Tories.

Scott Brison, the Liberal finance critic, told the Globe and Mail that speculation was "hyperactive" about a possible non-confidence motion.

"The rumour mill is on overdrive on this," he said. "We're waiting for the Speaker's ruling. We'll determine then what steps are appropriate after that."

The Speaker is expected to rule at any time on two separate claims by Liberal MPs that the Conservatives have acted in contempt of Parliament.

One, from Liberal MP John McKay, relates to accusations International Co-operation minister Bev Oda misled Parliament and had a document doctored. The other, from Brison, asks the Speaker to find the government in contempt for refusing to fully disclose the cost of government crime bills.

If either ruling sides with the Liberals, they could then immediately move a motion of non-confidence in the government.

But Fife said that while the Liberals were determined to bring down Prime Minister Stephen Harper's government, it was far from clear that will give them a badly needed boost going into a campaign.

"They're certainly going to give it a very good try … but I'm not sure that it reaches out to ordinary people who are raising families and going to work every day," Fife said.

The Liberals want to focus voters' attention on a series of controversies and missteps by the Conservative government, rather than the economy, Fife said.

"It's harder for them to discredit the government on the economy … this is what the Conservatives want to run on. The opposition parties, particularly the Liberals, are looking for weaknesses and scandal to tar the government."

"I'm just not sure how much of that gets down to ordinary people on the streets."

The government is facing fierce opposition criticism over charges the federal elections commissioner has laid against four senior Tory officials over the $1.3-million "in-and-out" advertising affair during the 2006 election campaign.

And last week, Immigration and Citizenship Minister Jason Kenney came under attack after one of his aides inadvertently sent out a letter from the minister's office, as part of a fundraising plan to curry favour with South Asian and Chinese immigrant communities.