Earlier this year, police dispatchers in Evansville, Ind., received a chilling call. A man said he was holding his wife at knifepoint, and he warned police that he was heavily armed.

“I’ve spent the last two days arming my residence against forced police entry, and I’m armed to the teeth,” he told dispatchers over the phone.

The threat to the man’s wife wasn’t real. He was arrested for the improper 911 call while taking out the trash.

But the man wasn’t lying when he said he had a lot of guns. Police found 10 throughout his house, which they confiscated without a warrant under Indiana’s “Red Flag Law.”

More and more states are adopting so-called red flag laws in an attempt to curb gun violence. These laws allow police to confiscate guns in an emergency.

In Ohio, former Gov. John Kasich unsuccessfully pushed for the law last year, but the bill went nowhere in the Republican-led legislature.

Sam Preston has seen it used before.

“Quite often what it looked like would be deputies were responding to someone who's in crisis,” says Preston, who recently left the Vanderburgh County Sheriff’s Office after 30 years. “If there were weapons involved, they would take the opportunity to take the weapons with us.”

Indiana’s red flag law was passed in 2005 and is one of the oldest in the country. But it isn’t used a lot.

The Evansville Police Department thinks this is the first time it's taken guns under the law. Preston says the sheriff's office has used it about a half dozen times.

“I don’t think that anyone wants to live in a country where people can have their weapons seized and taken away from them,” Preston says.

Preston calls himself a Second Amendment supporter and says the law strikes a good balance.

“We also do have to protect the public, and just because someone at a moment in time may not be healthy enough for them to have a weapon, doesn't mean that down the road that they won't be able to," Preston says.

Indiana’s red flag law doesn’t require officers to obtain a warrant. Without one, police have to get a judge’s permission to hold onto the weapons.

Preston says judges almost always rule in favor of law enforcement, but the gun owner has the right to ask the court every six months to get the guns back. Many people whose guns are taken away under the law do eventually get them back.

“I think most of those crises are short-lived, and in particular talking about people about suicide," says Kent Leslie, who used to work for a local mental health center.

Leslie has taught classes on mental health issues to law enforcement, medical professionals and the general community. That included training to prevent suicide by limiting access to guns.

"When somebody’s at risk of dying by suicide, if we have some distance and time from the lethal means, it does save lives,” Leslie says.

He stresses that the vast majority of people with mental illnesses are not violent, and they’re much more likely to be the victim of violence than to perpetrate it.

Leslie says that law enforcement is part of larger network of family, friends and health care professionals working to prevent harm.

“I see the person that has a mental illness or that may be at risk of dying by suicide as the center of a wagon wheel and those spokes that surround that wagon wheel can help that person move forward,” Leslie says. "The more spokes, the better."

Just over half of suicides in the United States involve a gun. Leslie says red flag laws can help.

Even in a Republican state like Indiana, which recently hosted the National Rifle Association convention, laws like these have bipartisan support.

“It's common sense,” says Republican state Rep. Wendy McNamara. “We don't want dangerous individuals having access to guns, and if they do, we want to make sure that we find help for these individuals and that their weapons are taken away from them."

This year, McNamara co-sponsored some changes to the Indiana law, and they passed almost unanimously.

The new version allows state police to give the FBI the names of people who’ve had their guns taken away, and it’s now a crime to supply a gun to those people.

The changes come as other states turn to Indiana for guidance. Florida passed a red flag law following the school shooting in Parkland in February 2018. Colorado recently became the 15th state to pass one.

Though Ohio still has no red flag law of its own, Gov. Mike DeWine and Senate president Larry Obhof say they’ll look at the idea. Ohio pro-gun groups remain opposed to the measure.

“Indiana has been recognized because we were one of the originals having a Red Flag Law,” McNamara says. “A lot of people are looking to Indiana as they go and rewrite their laws on this type of process when it comes to taking away weapons from dangerous individuals."

Back in Evansville, a judge allowed police to keep the guns of the man who made the threatening 911 call. His case on the 911 call is still pending, and his lawyers didn’t respond to a request for comment.

But Evansville police say the law worked just as it was meant to.

This story was produced by Side Effects Public Media, a news collaborative covering public health.