On Saturday, the first meeting of Barca members' representatives under new club president Sandro Rosell voted 468 to 439 to pass a motion to bring the previous board to account in court.
"My board and I will contest the result of the general assembly because they have violated my right as former president to attend (the meeting) and to put forward our explanations," Laporta told a news conference.
"I stand by the accounts the board and I signed off. Our management was impeccable. The current board is responsible for the losses they have now. They have carried out a wretched reformulation (of the figures)."
Laporta stepped down after seven years at the helm in June, and was replaced by Rosell who won a sweeping victory in the presidential election.
On taking power in July, Rosell commissioned an audit of Barca's accounts and uncovered a post-tax loss of 77.1 million euros for the 2009/10 season.
That compared with a net profit of 11 million euros reported in June by the outgoing board of directors.
"This is the most important decision (taken by the members) in the history of the club," Rosell, who abstained from the vote, was quoted as saying on the Barca website on Saturday.
"There is nothing agreeable about it and personally I feel very uncomfortable with it all."
Barca director and board spokesman Toni Freixa responded to Laporta's news conference on Monday.
"The assembly was fully consistent with the law, and the measure was formally adopted in accordance with the law," he told Radio Catalunya.
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