HARRISBURG - Pennsylvania Attorney General Kathleen G. Kane will not defend a new law that effectively stripped municipalities of the right to enact their own gun measures, raising the prospect that the controversial statute might not take hold.

A spokeswoman on Thursday said Kane had exercised her authority to decline representing the state in a challenge to the law filed by Philadelphia, Pittsburgh, and Lancaster, and area lawmakers.

Instead, she is deferring to lawyers working under Gov. Corbett - who in six weeks will relinquish their offices to a new Democratic administration.

"The attorney general determined it would be more efficient and in the best interest of the commonwealth for the Office of General Counsel to handle this matter," said Kane's spokeswoman, Renee Martin.

Corbett spokesman Jay Pagni said the counsel's office would take on the case, but he also assailed Kane for what he called "another example of the attorney general refusing to fulfill her constitutional duty to defend the commonwealth and the people who elected her."

The law, which takes effect this month, granted out-of-state groups such as the National Rifle Association the right to sue municipalities that enact gun-related ordinances stricter than state law.

Critics said it was a backhanded way to cripple municipalities' efforts to enact their own measures by subjecting them to costly and time-consuming litigation.

Since its passage, four townships or boroughs in the state's southeastern corner have repealed ordinances that require residents to report lost or stolen firearms - measures they hoped would cut down on the flood of illegal gun sales.

Others are considering similar repeals, local officials say.

The challenge to the law, filed by State Sen. Daylin Leach (D., Montgomery) along with other lawmakers and the cities, argues that the firearms language in the law had no relation to the underlying bill it was amended to - one that increased penalties for stealing copper and other metals. The plaintiffs contend that violates the so-called "single-subject" rule for legislation stipulated by the state constitution.

The decision by Kane, a Democrat, comes 18 months after she declined to defend the commonwealth in another controversial lawsuit - that one over its ban on same-sex marriage. Corbett, a Republican and her predecessor as attorney general, then hired outside counsel to defend the law.

A federal judge eventually struck it down.

On Thursday, Leach praised Kane as "doing the right thing" in the gun case.

"She defends the state all the time, and the vast number of cases have credibility," he said. "But she is under no obligation to take an untenable position."

Although Corbett's lawyers can act on the case, a decision on how to proceed will likely end up before the counsel that Gov.-elect Tom Wolf installs after he takes office next month. A spokesman, Jeffrey Sheridan, said the Wolf administration would review all existing litigation upon taking office.

In Montgomery County, attorney Sean Kilkenny said three municipalities he represents - Whitemarsh, Jenkintown, and Norristown - have repealed their gun laws. Hatfield Township also repealed its law, and at least three others are considering it or are doing so.

Despite Kane's stance, Kilkenny said he would not advise them to delay or backtrack.

"The [state] law's still on the books, and the NRA could use it," he said. "Until the Supreme Court or someone else tells us otherwise, we're left with the law on the books."

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