OTTAWA Infighting over who is to succeed Jean Chretien caused an embarrassing breakdown in Liberal discipline yesterday and has exposed how badly the sparring has divided the ruling party, opposition members say. The vote for the chair of the Commons finance committee, normally an uncontested event because committees are dominated by Liberals, was split between backers of Roy Cullen, a high-profile supporter of Finance Minister Paul Martin, and of Sue Barnes. She, like most of the Liberals on the committee, is also said to support Mr. Martin but is considered far less ardent than Mr. Cullen.

Liberal Whip Marlene Catterall, whose task it is to ensure that all Liberals vote as the Prime Minister wishes, took extraordinary and "heavy-handed" steps to have her candidate, Ms. Barnes, elected, committee members said.

"Maybe it was a question of the Prime Minister's Office reasserting, and getting their candidate in," Mr. Cullen told CBC Newsworld. "When we say that committees are masters of their own fate, it's a little suspect."

Mr. Chretien has not been supportive of Mr. Martin's unofficial bid for his job. Leadership politics have reached a fevered pitch in the past 10 days, with caucus members electing Stan Keyes, an outspoken Martin supporter, as their national chairman, and with a nasty public dispute between Mr. Martin and rival Allan Rock over party membership rules. The orchestrated election of Ms. Barnes was a sign Mr. Chretien is flexing his muscles, some panel members said.

Before the election, the whip took the puzzling step of trying to pressure opposition MPs -- New Democrat Lorne Nystrom and Progressive Conservative Scott Brison -- into supporting Ms. Barnes, the two MPs said. Ms. Catterall suggested to them that they would be wasting their votes if they supported Mr. Cullen, because the whip would merely pull him from the post if he won, the MPs said.

"I think it's a Martin thing. It's a leadership thing," Mr. Nystrom said.

The MPs said they were "repulsed" by the "toxic levels of Liberal thuggery" that have led Liberal operators to believe they not only control their own back bench but also those of the opposition parties.

"It looks like anyone too close to Martin didn't get promoted," one Liberal insider said.

The insider, as well as the two opposition MPs, said they overheard another Liberal MP, Sophia Leung -- who is also the parliamentary secretary to the Minister of Finance -- complain out loud that the whip had threatened to take away her secretary position if she didn't vote for Ms. Barnes.