By Pat Loeb

HARRISBURG, Pa. (CBS) — Pennsylvania’s attorney general says she won’t defend a controversial new state law that prevents local governments from regulating guns within their municipal borders.

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The cities of Philadelphia, Lancaster, and Pittsburgh, along with several state legislators have challenged in Commonwealth Court the law that allows the National Rifle Association to sue any municipality that passes gun control measures stricter than state law — such as Philadelphia’s requirement that gun owners report a lost or stolen firearm.

But proponents were unable to pass the measure in the state legislature on its own, so they tacked it in to a bill about scrap metal theft.

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Challengers say that violates the state’s “single subject” rule, and state senator Daylin Leach (D-Montco/Delco) says attorney general Kathleen Kane is wise not to defend it.

“These things have nothing to do with each other; for her to go to the court and say they did have something to do with each other would make her lose credibility in all the future cases,” Leach said today.

Kane has turned any future defense of the law over to the office of the general counsel, as she did when she declined to defend the state’s same-sex marriage law.  The state lost that case.

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All members of the state’s office of general counsel will be up for review when Tom Wolf is inaugurated as governor next month.