A lawyer for the NCAA and four sports leagues says New Jersey's move to drop a prohibition on sports betting violates federal law and the state's own constitution.

Lawyer Jeffrey Mishkin made his arguments Thursday before a federal judge who is considering whether legal sports betting can begin in the state.

Gov. Chris Christie has signed a law that would allow sports betting at casinos and horse tracks. One track is preparing to open a sports book. Theodore Olson, a lawyer for the state, says it is not seeking to authorize, establish or regulate sports gambling, but rather ending a ban.

But Mishkin says the state does want to authorize sports betting because it would restrict it to the casinos and tracks, bar those under 21 from participating and continue to ban betting on games involving New Jersey college teams.

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