Philadelphia’s legal battle to enforce an ordinance that would fine people who don’t report their lost and stolen guns began to take shape Thursday. Though the bulk of the hearing was spent with both sides laying out their arguments, the presiding judge ruled two mothers who lost their sons to gun violence will be able to testify about their experience.

The “Failure to Report Lost or Stolen Firearms” law was passed in 2008. Lawmakers and gun safety advocates argue the sooner law enforcement knows of a missing firearm, the sooner they can get it off the streets.

Still, the city never enforced the measure until November of last year as questions loomed over the ordinance’s legal standing.

In May of 2018, a gun under Rashad Armstrong’s name was found with someone else during a Lancaster traffic stop where police found drugs. Armstrong would go on to tell authorities he’d lost the gun a month prior, but he never reported the firearm missing.

On Thursday, Armstrong’s attorneys sought a permanent injunction, arguing that only the General Assembly can regulate guns, citing case law in support of their argument. Armstrong’s legal team argues preemption prevents the city from enforcing the ordinance against Armstrong or any other Philadelphian.

“This is just another occasion of the city of Philadelphia violating an individual’s rights and it’s time for us as a country to stand up when the municipal movement starts to violate our rights, especially our constitutional rights,” said Armstrong’s attorney, Joshua Prince of the Firearms Industry Consulting Group.

Prince argued that regardless of the city’s well-meaning intentions to reduce gun violence, the city’s only recourse is to petition the lawmakers in Harrisburg to change state laws.

But Ben Geffen, one of the Public Interest Law Center’s attorneys teaming up with the city’s legal team to fight the injunction request, pushed back.

“State law does put some restrictions on how some local governments can regulate guns, but it doesn’t completely eliminate the power of cities to do anything about gun violence,” he said.

Geffen is representing nonprofits working to reduce gun violence in the city, as well as mothers Kimberly Burrell and Freda Hall.

Both women’s sons were shot to death. The guns used in the killings were obtained illegally from sources in Philadelphia. The women believe enforcing the law could prevent murders.

“Law-abiding, responsible gun owners who lose a gun or whose gun is stolen call the cops and report it,” said Geffen.

The idea behind the ordinance is to discourage people who can legally buy guns from selling them to people who can’t legally carry — a process referred to as straw purchases.

When these illegally sold guns are used in a crime, the sellers avoid liability by claiming the guns in question were stolen, argue gun safety advocates.

Under the law, in addition to a fine up to $2,000 for failing to report the loss or theft of a firearm, the District Attorney’s Office can prosecute repeat offenders who can be jailed for up to 90 days.

But the legality of the measure has been in question since its inception.

Former District Attorney Lynne Abraham said she testified against the law when City Council considered it more than a decade ago.

In question then, and now, is whether the city is overstepping the General Assembly’s power to regulate guns and ammunition.

Abraham never enforced the 24-hour reporting requirement. Neither did Seth Williams, the District Attorney who succeeded her.

Gun control advocates found an ally in current District Attorney Larry Krasner, who partnered with the City Solicitor’s Office last January to investigate and prosecute offenders.

In addition to allowing mothers affected by gun violence to testify in April, the judge presiding over the case allowed local trauma surgeons to submit testimony Thursday on the toll gun violence was taking on hospitals.

The hearing will resume on April 22, but Geffen expects a long fight.

“We also believe that this is a case that will go up on appeal to the Commonwealth Court and finally the Pennsylvania Supreme Court,” said Geffen.