D.C. Attorney General Karl Racine says in a new court filing that Metro is too sensitive a place to allow regular commuters to carry handguns, because trains and buses carry large numbers of federal workers and also D.C. school children on a daily basis.

Racine made the arguments in a court filing last Friday afternoon in response to a late-June lawsuit by four people seeking to carry guns in the public transit system. Their federal lawsuit came only days after the Supreme Court dramatically altered the legal standards for prohibiting guns in public places, ruling that any such restrictions or bans have to be rooted in the country’s historic traditions and cannot simply be justified by a significant government interest.

In the June lawsuit, the four plaintiffs — three D.C. residents and one Virginia resident — said they wanted to carry concealed handguns on trains and buses in D.C. for personal safety and that Metro should not qualify as a “sensitive place” like a school or polling place, where a ban on carrying guns is more constitutionally permissible.

But in his 44-page response, Racine argued that Metro is in fact a sensitive place because of the role it plays in transporting government workers and school children (since D.C. has no school buses, children use Metro for transportation) but also because of the possible risks of conflict on crowded trains and buses.

“In dense spaces characterized by jostling and interpersonal conflict, the risk of a gun being accidentally discharged or hastily fired is tragically high — not only for the innocent bystanders who may be shot, but also for the countless other victims who may be crushed or thrown from a platform by a panicked crowd. What is more, any incident involving a firearm could disrupt transit for the hundreds or thousands of people relying on government-provided transportation each day,” he wrote. “In addition, the Metro is a sensitive place because it functions as the District’s school bus, meaning that a large concentration of children may be riding trains and buses at any given time.”

Racine also countered historical arguments made by the plaintiffs to justify being allowed to carry concealed guns on Metro, saying that the conditions faced today are little like those early in the country’s history. “Plaintiffs provide no sensible reason to assume that the desolate roadways of 19th century are at all analogous to the Metro’s gated, underground, and densely packed transit zones,” he argued.

The city’s response to the lawsuit argues against the plaintiffs’ request for a preliminary injunction and summary judgement declaring the Metro gun ban unconstitutional. Racine said the plaintiffs have not met the bar for such a quick ruling, and that a judge should either dismiss the lawsuit or allow the city officials time to “conduct their own research into historical tradition and relevant historical analogues.”

The likely impact of a ruling against D.C.’s Metro gun ban has also attracted the attention of the federal government. Last week the U.S. Department of Justice indicated it was considering joining the case because it possibly “implicates important questions regarding the interpretation of the Second Amendment and significant equities of federal agencies.”

D.C. broadly prohibits open carrying of handguns and restricts where people with concealed-carry permits can go. Currently, someone carrying a concealed handgun cannot enter government buildings; schools or universities; polling places; libraries; hospitals; public transportation; stadiums or arenas; many business that serves alcohol; the National Mall, U.S. Capitol, and around the White House; or within 1,000 feet of a protest or dignitary who receives police protection. (There are roughly 4,000 people in D.C. with concealed-carry permits, split evenly between D.C. residents and non-residents.)

But ever since the Supreme Court’s June ruling there have been a flurry of lawsuits challenging D.C.’s strict gun laws, which have largely been shaped by past litigation — including the 2008 Heller ruling that overturned D.C.’s longstanding ban on handgun ownership and later legal fight that forced the city to allow people to carry concealed handguns outside their homes.

Along with the Metro gun ban case, a separate lawsuit filed in June takes aim at the city’s limit on how much ammunition a gun owner can carry with them, and one from August seeks to overturn the city’s ban on high-capacity magazines. Earlier this month, another lawsuit was filed challenging D.C.’s ability to deny a concealed carry permit to people deemed to pose a risk because of their “propensity for violence or instability” or a “history of violent behavior.”