If someone stops a potential murder by subduing a gunman, what would be the possible consequences?

Question

I'm writing a story and I wanted some accuracy on this matter, specifically for the consequences on the person to whom this would happen.

Imagine an off-duty security guard, while walking home, finds a man pointing a gun at an unarmed man and child. The security guard physically fights, restrains and cuffs him, and calls for law enforcement, saving the victims from getting shot.

Would the security guard be arrested for vigilantism? Will this go to trial or would they be let loose without needing to call an attorney?

Would anything change if the would-be murderer was a rogue cop or soldier?

What would realistically happen to this person, legally speaking?

Answer 1

He would be thanked and sent on his way. We don't generally punish people for preventing murders, even if they are rogue cops or soldiers.

If you wanted him to plausibly land in legal peril, he'd probably need to do more than simply save someone's life. The most obvious possibility, I think, would be if he were to continue inflicting harm on the attacker after cuffing him. At that point, there's probably no justification for a continued use of force, so he could face assault charges there.

Also possible would be that the way he handled the situation -- the amount of force he used, the failure to de-escalate, failing to call for assistance -- just violates some police or military policy. I don't know if that would jam him up in the way you're looking for, though.

Answer 2

Would the cops arrest the man for vigilantism?

There is a defense of others justification in the criminal codes that expressly justifies this kind of conduct.

Will this go to trial or would he be let loose without needing to call an attorney? What would realistically happen to this person, legally speaking?

He would be let loose, after getting contact information and providing a statement. If the case went to trial, he would be called as a witness. The police would probably release a positive press release and reporters would try to interview him.

Edit: Would anything change if the would-be murderer was a rogue cop or soldier?

Same result if he was a "rogue cop."

The posse comitatus statute in the U.S. prohibits use of the military for law enforcement. So, a criminal violation of that statute is possible if this was ordered by a commanding officer as part of the soldier's official duties rather than in his capacity as a mere citizen bystander.

But, in a role as a mere citizen bystander a soldier would be let go and highly praised. Don't trust me on that. It has really happened:

An Islamic State operative accused of an attack on a European train that was stopped by three young vacationers from California went on trial Monday in France on terrorism charges.

Opening the trial of Ayoub Khazzani, the judge said that the 31-year-old Moroccan, who had ties to a notorious terror mastermind, intended to “kill all the passengers” aboard the fast Amsterdam-to-Paris train in 2015 but “lost control of events.” One of the young men who helped subdue Khazzani told investigators that the shirtless gunman seemed high on drugs and “completely crazy,” the judge said.

The dramatic story of how Khazzani was brought down by the three American friends was turned into the Hollywood thriller “The 15:17 to Paris” by Clint Eastwood. Khazzani’s trial is expected to last a month, with testimony expected from the two U.S. servicemen and their friend, who were hailed as heroes and granted French citizenship.

Eastwood has also been summoned to appear Nov. 23. It’s unclear whether the four men will testify in the Paris courtroom or by video.

During the failed August 2015 attack, Khazzani swaggered bare-chested through the train with an arsenal of weapons. He shot one passenger before the trio of traveling Americans — Alek Skarlatos, Spencer Stone and Anthony Sadler — tackled and helped subdue him.

(Los Angeles Times November 16, 2020)

UPDATE: Misunderstood the edit.

First of all, your criminal and civil liability depend upon your intent. If you in good faith believe someone not in uniform to be a criminal, when in fact, the person is an undercover cop or a soldier, the analysis wouldn't change because you wouldn't realize the situation.

Generally speaking, a private citizen does not have the authority to interfere with someone known to be a law enforcement officer acting in the course of their official duties, and is obligated to follow the law enforcement officer's instructions in those circumstances, so the risk of liability is much greater in that situation. Essentially, while you could act lawfully if you knew that the law enforcement officer was acting unlawfully and you were preventing a crime, it would be much, much harder to prove that your actions were justified. The police might arrest you, at least until matters are cleared up. The law enforcement office would argue that he was effecting a lawful arrest, not trying to murder someone, and that you assaulted and falsely imprisoned a law enforcement officer (crimes that carry enhanced sentences), and usually a policeman is going to win a credibility contest over an ordinary citizen at trial when the accounts differ (although the fact that you and the two people you saved would have the same story would help and there might be other context providing a motive for an attempted murder that would help).

The case of a soldier would be easier. A soldier does not generally have the power to pull a gun on someone in the U.S. in peacetime, or to engage in law enforcement, or to direct a civilian to help him (although an activated national guard member would be an exception). So, it would be pretty simple to determine that a soldier, even in uniform, is acting unlawfully, in an unofficial capacity, as a criminal, which would authorize the civilian to act in defense of others. Once the police come, it is likely that the soldier would be remanded to the military and subjected to a court martial rather than to the civilian justice system, so the intervening individual might be called to be a court martial witness rather than a civilian court trial witness. In the case of an activated national guard member during some kind of emergency, however, the issues presented would be similar to those of a civilian rogue law enforcement officer.

Answer 3

Vigilantism is when someone actively seeks out people they consider to be "evil doers". Someone who chances across a crime, and uses just enough force to prevent the crime, is not a vigilante. Also, vigilantism is itself not a crime; rather, it often involves people committing acts that are otherwise crimes. For instance, citizen arrest laws generally require actually witnessing the crime, so physically restraining someone because you think it's "likely", or you've "deduced" that they committed a crime, is illegal. And of course, physically assaulting someone in retaliation for an alleged crime is illegal.

There's a difference, though, between whether someone's actions fulfills the elements of a crime, and whether they can be investigate/charged with a crime. If there's any doubt as to whether this person has committed a crime, the police would likely detain him. With three witnesses (including himself) supporting his story, it's unlikely that the government would charge him with a crime. But if the government had some bias, it may pursue charges, and the gunman being a cop would be a reason for bias.

Answer 4

Would the cops arrest the man for vigilantism?

Quite the opposite: The police will ask him for his written account of what he saw, heard and did - and if there's a trial he will probably be called as a prosecution witness to give oral evidence.

It's also possible that he could get some form of civic-duty recognition like a commendation for bravery.

Edit: Would anything change if the would-be murderer was a rogue cop or soldier?

I can't see any reason why the suspect's occupation would affect the legality of his actions. He may encounter more resistance, but as long he uses only reasonable force in the circumstances to detain the suspect (e.g. by not beating him with a nightstick when he's 'cuffed on the ground) his actions are seemingly totally justified and lawful.

Answer 5

• The law and the practice might differ.
  In many parts of the world, somebody who performs a citizen's arrest against an off-duty cop would be in trouble. The cop would proclaim to be innocent, and other cops would tend to believe their buddy.
  At the very least, the would-be hero would be detained and questioned until his innocence is shown.
• Even in law, there might be a presumption that cops are in the right until proven wrong in court. Off-duty police might be allowed/required to place themselves on duty if they see a crime in progress, and step in. That means the would-be hero would be detaining an on-duty cop.

Answer 6

Almost certainly they would be lauded for their service and requested to testify against the gunman. It really doesn't matter if the person who stops them is a random civilian or a security guard, or if the perp is a soldier or whatever.

https://www.nbcsandiego.com/news/local/good-samaritans-tackle-suspected-shooter-in-gaslamp-quarter/2586328/

“When I got close enough to the guy [McKeon] that was following him, I asked him, ‘Is this the guy? And he nodded his head, yeah. So, I just sprinted and tackled him,” Larrabee said. No words were spoken. Larrabee said he never saw the 9mm handgun that police said had been tucked in the man’s waistband. San Diego Police Department Chief David Nisleit said they were then joined by a third person, before officers arrived and struggled to take the suspected shooter into custody, eventually tasering him before being able to do so.

Larrabee said they were handcuffed and put in police cruisers until officers could figure out who was the suspected shooter. “They were not messing around because there was a gun involved, you know what I mean?” Larrabee said. Nisleit said the actions of the Good Samaritans may have saved lives.

Things would get more interesting if the crime or attempted crime was much more minor in nature, though. You probably wouldn't want to citizens arrest someone for shoplifting an item of low-value, for example (which is exactly why you may have seen recent videos of shoplifters running past security guards without any attempt to stop them).

Answer 7

rogue cop

This is where you run into trouble. All countries with armed police have cases of cops shooting unarmed people, and of cops threatening to shoot unarmed people; but this does seem to be worse in the US than in Europe. (Yeah I know, citation needed.) Smartphones often help to level the playing field by making this public, but that doesn't stop it happening at the time. Of course the US isn't the worst here; many South American countries have had police "death squads", and some still do, but those are really paramilitaries rather than police.

So the trouble starts when the cops arrive and recognise their colleague. Who are they going to believe? Unless someone's filmed this, chances are they'll believe their colleague and not the security guard or victims, so our hero is likely to be spending some time in the cells. It seems unlikely that the case would go to trial - the cop won't want the publicity, for one thing - and there would maybe be some internal investigation into the cop, but it's highly likely that nothing would happen.

or soldier

This is a bit more clear-cut. Unless there's a state of emergency and martial law declared, then regular soldiers have no authority to be carrying a loaded weapon on the street. Armies tend to be unhappy about soldiers taking weapons without permission and wandering the streets with them, threatening civilians. Unless this is some special-ops thing and the victim is someone of political significance, of course, in which case plot happens.

There are more possibilities than just police or soldiers though. The "murderer" could be DEA/BATF/FBI, and the "victim" could be a drug-runner/gun-runner/kidnapper. Again, pick your categories and then plot happens.

Answer 8

Note: This doesn’t aim to answer the original question but might help the OP to find a path forward in case OP really wants to pursue the story from a legal standpoint or the struggles of the legal system as it relates to this character; I’m assuming this part of the story is crucial in some way.

As others have stated, the saviour would not be (in most states) legally punished but you could twist the story a bit to make it so. Also, this question might be better to ask on WorldBuilding stack

If this was a targeted attack, the assailant or their organization could pressure the victim to testify against the saviour and turn the story around. This could be twisted many ways but an example could be that the saviour was made to be the assailant and that the original attacker was trying to save the two civilians. The organization could go as far as offing the original attacker to raise the legal matter to murder in the first degree or working with the attacker to increase bruising, cuts, maybe even a bullet wound or two and claiming victim.

It could also be harder to fight such a charge against the saviour if he had already committed a crime in the past, maybe battery with a weapon or a domestic.

Basically, if you build the story right, the saviour doesn’t need to be in trouble legally for his actions; instead he’d be in a legal battle to prove his innocence against organized crime.