reports that a retiree filed a lawsuit with the U.S. District Court in Southeast Michigan yesterday challenging the deal that has been struck between General Motors and the United Auto Workers union. The lawsuit argues that the UAW did not have the legal authority to use millions of dollars in hourly retiree benefits as bargaining chips with GM, and also says that GM had no right to take those benefits away after they had been in place for so long.

The deal included an increase in out-of-pocket healthcare costs for retirees, among other changes. The filing brought to light details that had previously not been made public, including an expiration of the agreement in 2011 unless both parties agree to extend it.