HARRISBURG - In a case that could have far-reaching consequences for the future of public parks and municipal authority throughout the state, the Pennsylvania Supreme Court on Wednesday heard oral arguments in a more than seven-year dispute over a Chester County town's proposal to sell 28 acres of parkland to a developer.

At issue is whether Downingtown Borough can sell several parcels of its parkland for the construction of retail space and about 300 housing units in what is now the roughly 48-acre Kardon Park, which crosses into East Caln Township, Chester County.

"People are probably running through it right now," said H. Fintan McHugh, one of the attorneys representing residents and one Borough Council member who oppose the sale, who argued that the land is restricted for public use and that the county court should decide the case.

Robert Byer, attorney for the developers, pointed out that a minimum of 20 acres would remain parkland. He argued Downingtown has the authority to sell the property, which borough officials have sought to develop for more than two decades, saying it will generate at least $100,000 annually in tax revenue. Officials also say it will stimulate retail and residential growth in the 8,000-resident borough.

Byer argued that the Eminent Domain Code and other state laws allow Downingtown to decide whether to sell the property.

"The General Assembly has made the rules in this area," he said.

McHugh disagreed on the ways the statutes and codes apply to Kardon Park and similar parkland.

"This is such an important case," McHugh said after the hearing. "There are hundreds of parks that could be sold without any court review or public participation."

Samuel Stretton, McHugh's cocounsel, told the justices that if they rule Downingtown has the power to sell its public parkland without court review, "you're going to lose all parkland."

"These municipalities are cash-strapped," he said.

The projected purchase price of the parkland is $3.1 million, according to developer Sarah Peck, president and managing partner at Progressive Housing Ventures.

Downingtown officials and developers entered into a sales agreement in 2007. They and those opposed to the sale have been facing off in court since 2009. Commonwealth Court decided in April 2015 that Downingtown can sell certain parcels in the park but not others without the Orphans' Court approval. Both sides appealed to the state Supreme Court.

Peck said borough officials elected by taxpayers, not the courts, should decide how to use public land.

Her proposed mixed-use development would include public space and additional walking trails, at least doubling the amount of "usable open space," she said. She also would cap soil that contains arsenic and other contaminants from when the land was used as a landfill in the 1960s.

"It's a perfect way to have your cake and eat it too," Peck said of the borough's decision to sell to her.

The justices did not indicate when they would rule.

610-313-8207 @MichaelleBond