NDP Leader Lorraine Michael supported changes to election law in 2007 that her party now says are unconstitutional.
Michael blames a lack of research support at the house of assembly and the swift passage of legislation for not picking up on potential problems at the time.
"In 2007, I had two caucus staff," Michael told CBC News. "We were very limited in the research ability that we had. And if I had had access to more legal advice at that time, I very well might have picked up on what I'm picking up on now."
'Yes, I have changed my mind, because the practice of 2007 and especially the practice of 2011 have shown me that it is wrong.'—NDP Leader Lorraine Michael
A lawsuit filed by defeated NDP candidate Julie Mitchell asserts that Newfoundland and Labrador's special ballot provisions "are a violation of democratic and constitutional norms of Canada and the Commonwealth."
Mitchell lost to Progressive Conservative cabinet minister Clyde Jackman by just 40 votes in the south coast district of Burin-Placentia West in the Oct. 11 election.
The NDP's lawsuit — filed at Newfoundland and Labrador Supreme Court — is sharply critical of changes to election laws that allow voters to cast special ballots up to four weeks before the writ is dropped for an election call.
But Michael had no problem with that change to special ballot rules when it was debated in the legislature four years ago.
"... This makes sense when we are talking about the general election because we know the date of the general election," Michael said in the house of assembly on June 4, 2007. "We know exactly when four weeks before is going to be."
Fast forward to today, and Michael says legislation zips through the legislature much too quickly.
"With regard to this bill, second reading and committee of the whole all happened in the same day," she said. "I don't think that we give the opposition parties the time to carefully study the legislation that is put in front of us."
She acknowledged that she has since reversed her opinion on the special ballot issue.
"Yes, I have changed my mind, because the practice of 2007 and especially the practice of 2011 have shown me that it is wrong."
The pending court action is the second one aimed at overturning the tight Burin-Placentia West race. A Supreme Court judge previously rejected an NDP bid for a recount.
Asked if she is worried about the party being viewed as sore losers, Michael said: "I hope that people will not look at it that way. Whether they do or not, I believe that we have a responsibility to bring it forward."
Tories slam 'flip flop'
But the governing Tories were quick to criticize Michael, saying her "flip flop" on the issue shows a lack of principles and a lack of responsibility by blaming staffing levels.
"It is obvious that the NDP are so desperate to become the Official Opposition that they have no problem tossing aside the will of the people who voted by special ballot," Jerome Kennedy, the government house leader, said in a press release.
"Ms. Michael is essentially saying to those voters, your votes do not count and I will not respect the choice you made on election day. For a party which has said democracy can only be served with the house of assembly open, their willingness to disrespect the decision of voters when it is convenient for them is particularly hypocritical."
The NDP'S constitutional case is scheduled to be heard on Dec. 13 in Newfoundland and Labrador Supreme Court.
Meanwhile, the Canadian Civil Liberties Association has filed an application seeking intervenor status in the matter.