Second Amendment advocates are asking the Supreme Court to rule on a Hawaii gun law they say blocks people who legally carry concealed firearms from carrying them in most public spaces. They say the law is so broad that it would ban concealed weapons across almost the entire island of Maui.

The law makes it easier to get a concealed weapons permit but simultaneously bans guns in public places like hospitals, stadiums, bars, parks, and movie theaters. Private businesses also have to post a sign indicating whether they allow guns inside.

“You essentially don’t have a right to carry a firearm if the law covers 96.4 percent of publicly accessible land,” a lawyer for the plaintiffs, Alan Beck, says. He adds that the law is so broad that a hunter can’t carry a handgun for self defense while they are hunting with a rifle.

A group of 25 states and the Arizona legislature submitted a brief on Monday asking the high court to take up Wolford V. Lopez. The National Rifle Association and other gun rights groups and the Justice Department, which has announced a review of its position in gun cases, have also filed briefs supporting the challenge.

The governor of Hawaii, Josh Green, signed the law in 2023 in response to the landmark 2022 decision in New York State Rifle and Pistol Association v. Bruen. That ruling struck down a century-old state firearms regulation requiring that a citizen had to show a compelling need to obtain a firearm license.

Hawaii and four other states, including New York and California, passed similar laws requiring businesses to publicly post whether firearms are allowed on their property or it is illegal for a permitted gun owner to carry a firearm on it.

Referred to as the default rule because it automatically bans guns unless the business takes action, it is central to the case advocates hope to get before the court.

“As a practical matter, no business is going to do that,” Mr. Beck says of the requirement to post notice. “It’s such a politically charged issue.” He says business owners are concerned about scaring off customers even if they are OK with people carrying concealed weapons.

The Second Amendment Foundation says the sign requirement runs counter to the right to carry that’s clearly expressed in the Bruen case. “The intent is obvious and the results disastrous to the right to carry in public,” the group’s director of legal operations, William Sack says.

The law has never been enforced because it was blocked by an injunction eight days before it was set to go into effect. “We have evidence nothing bad is happening because people have been carrying for two years without incident,” Mr. Beck says.

The executive director of the Duke Center for Firearms Law, Andrew Willinger, says the Justice Department getting involved might make the case more attractive to the Supreme Court to decide on the default rule.

“That does substantially increase the chances that the court may start here,” Mr. Willinger says.