OTTAWA - Liberals are calling for Prime Minister Stephen Harper to testify at the House of Commons justice committee about comments that sparked the Chuck Cadman affair.

But committee chair and Tory MP Art Hanger won't stay in the room long enough to let parliamentarians vote on the matter.

About 10 minutes into Tuesday's meeting, Liberal MP Dominic LeBlanc asked the committee to vote on his motion to probe allegations Cadman was offered financial inducements before a historic Commons showdown.

Bloc Quebecois MP Real Menard seconded that request.

Hanger apologized to several witnesses who had flown in from across the country to appear before the committee.

Then, he abruptly left the room to the surprise of the witnesses and the recriminations of the Liberals and Bloc.

It's the third time Hanger has left the room to avoid a vote.

The MP from Calgary has said studying the Cadman affair falls outside the justice committee's mandate.

LeBlanc says Opposition MPs are prepared to vote no confidence in Hanger -- in which case, another Tory MP on the committee would replace him.

Then-Opposition leader Harper told Cadman biographer Tom Zytaruk in September 2005 that a pair of party operatives offered the Independent MP "financial considerations'' on the eve of a historic confidence vote.

The Liberals want Harper to explain what he meant by "financial considerations.''

Cadman's widow maintains the two Tories offered her husband -- who died of cancer two months after the vote -- a million-dollar life-insurance policy. Harper's communications director "categorically'' denied it.

Dona Cadman -- the Tory candidate in her late husband's B.C. riding -- says she considers the alleged offer a bribe.

But she said Harper convinced her years ago he knew nothing about the alleged life-insurance offer.

The Conservatives have denied allegations that party stalwarts Tom Flanagan and Doug Finley made Cadman a financial offer during a meeting on May 19, 2005.

LeBlanc wants Flanagan and Finley to appear at committee to face questions about what happened that day.

He also wants to call Harper's chief of staff, Ian Brodie, Natural Resources Minister Gary Lunn and party elder statesman John Reynolds to testify.

Harper filed a $2.5-million lawsuit last month against the Liberal Party of Canada, the Federal Liberal Agency of Canada and the unnamed author, or authors, of statements published on the party's website.

The articles were headlined "Harper knew of Conservative bribery'' and "Harper must come clean about allegations of Conservative bribery.''

Meanwhile, the RCMP is considering its own investigation, but the force hasn't confirmed or denied its intentions.