A woman gathers a pile of signs as she leaves the Pennsylvania state Supreme Court on Wednesday in Pittsburgh. The court was hearing arguments from seven municipalities challenging portions of a new law that regulates natural gas exploration. The law is known as Act 13.

PITTSBURGH — The Pennsylvania Supreme Court had an unusual standing-room-only crowd Wednesday, as lawyers debated a new law that regulates the state’s booming natural gas industry.

Representatives of seven municipalities say the law, known as Act 13, takes away their ability to control gas drilling operations through local zoning, leaving them defenseless to protect homeowners, parks and schools from being surrounded by drilling sites or waste pits.

“It is the role of the court to address whether the legislature went too far,” said Jordan Yeager, one of the lawyers representing the municipalities.

In July, the state Commonwealth Court ruled 4-3 that the zoning aspects of Act 13 violated the state constitution, and Gov. Tom Corbett’s administration appealed. The Supreme Court currently has three Republicans and three Democrats, and cannot overturn a lower court decision on a 3-3 tie vote.

The Corbett administration says the sweeping, eight-month-old law is constitutional and doesn’t violate the rights of municipalities or residents. Matthew Haverstick, one of the lawyers representing the state, noted municipalities are created by the Pennsylvania General Assembly.

“When the general assembly wants to, it can override local zoning,” Haverstick said. “I think the analysis stops right there.”

But several justices questioned whether the power of the legislature is unlimited.

“Isn’t the whole purpose of zoning to protect neighbors?” Justice Max Baer asked. “There’s a point where government can go too far.”

Justice Thomas Saylor questioned whether the law “could in effect turn private residential communities into industrial zones,” and Justice Seamus McCaffery asked “about the constitutional right of the citizenry for quiet enjoyment” of their property.

Some local officials say Act 13 puts them in a difficult legal position, because part of their job is to protect the health and safety of their communities.

“We believe Act 13 clearly violates the Pennsylvania constitution and makes it impossible to carry out the responsibilities of elected office,” Robinson Township supervisor Brian Coppola said in a statement.

Haverstick suggested the high court “must defer to the policy of the legislature,” prompting Baer to interrupt and say “I have problems with that.”

Jonathan Kamin, another attorney for the municipalities, added that “everyone else has to follow the rules on local zoning,” and claimed that “since the 1880s there has not been one industry” that has been given the broad rights granted under Act 13, which allows companies to drill and put waste pits even in residential areas.