Baseball bat manufacturers and school baseball sponsors teamed up Monday to ask a judge to toss out a law banning metal bats in the city's high school games as unconstitutional.

The lawsuit against New York City was filed in U.S. District Court in Manhattan just days after the City Council overrode a mayoral veto to let the law be enforced beginning in September, according to the Associated Press. The lawsuit was filed by USA Baseball, a Raleigh, N.C.-based national governing body for several baseball associations, and The National High School Baseball Coaches Association, based in Tempe, Ariz., along with four sporting goods companies and several fathers of ballplayers.

Among the plaintiffs in the lawsuit were Easton Sports Inc.; Wilson Sporting Goods Co.; Rawlings Sporting Goods Co. and Hillerich & Bradsby Co.

The lawsuit says the rule would harm players, coaches, schools and bat makers by increasing the costs and making the game less competitive and less fun.

The lawsuit maintains the law is an unlawful exercise of legislative power, violating the Commerce Clause of the Constitution by isolating New York City players and teams from those of other states who can use metal bats.

The law also violates the due process requirements of the Constitution because it bears no rational relationship to a legitimate governmental purpose and is arbitrary and invalid, the lawsuit said. It also claimed the law violates the Civil Rights Act and discriminates against the use of metal and nonwood composite bats without any rational basis.

U-S-A Baseball is the national governing body for several baseball associations. Mayor Michael Bloomberg vetoed the bat ban last month, saying it was an issue for those who run youth leagues, not the government. The City Council then overwhelmingly overrode the veto.

Proponents of the new law — set to take effect in September — say metal bats increase the risk of injury because they cause balls to move faster, giving young players less time to react. But an American Legion Baseball study in 2005 found no substantial scientific proof that wooden bats are safer than metal bats.