A California court ruled the Second Amendment does not guarantee the right to carry concealed weapons in public.
The case could have a ripple effect across the country.
The 7-4 ruling from a federal appeals court in San Francisco overturned a prior decision, much to the dismay of gun advocates. If challenged, the case could make it all the way to the Supreme Court.
"We hold that the Second Amendment does not preserve or protect a right of a member of the general public to carry concealed firearms in public," wrote Judge William Fletcher in his majority opinion.
"Since the 1830s, courts have pretty consistently said that the right to carry -- concealed -- is not part of the right to arms," said David Kopel, Associate Policy Analyst with Cato Institute.
The ruling upholds a California law requiring people applying for a concealed carry permit to show "good cause."
"Carrying concealed was viewed as something kind of suspicious, where maybe you're trying to sneak up on somebody, so the traditional understanding of the right has been open carry," said Kopel.
In most of the country, you need a permit to carry a concealed weapon, but there are some exceptions. States like Arizona and Kansas do not regulate it.
"In most of the country, the right to arms is protected, and people can carry openly or concealed, depending on the legislative preferences," said Kopel.
Gun advocates are upset by the ruling.
"This decision will leave good people defenseless," said the executive director of the NRA, in a statement.
Right now, the Supreme Court is without a tiebreaker vote after the death of Justice Antonin Scalia.