Citizen's arrest laws in the US are murky, to say the least. They're decided on the state level, meaning they're different everywhere you go. Regardless of where you live, there are so many factors that go into whether the heroic citizen's arrest you're conducting isn't itself a crime. Is the suspect conducting a felony or misdemeanor? Did you actually witness it? Did you use reasonable force to detain the suspect? It's no wonder police would rather we leave the arresting to them.
Even though citizen's arrest rules vary, there are a few general truths about it, as this list outlines. But if you really want to know how citizen's arrest works in your state, please contact a lawyer or local law enforcement. This list is for entertainment and informative purposes only: it's not legal advice, but a general collection of facts and information on citizen's arrest in the US.
Law Enforcement Doesn't Want You to Do It, Would Rather You Leave It to Them
One of the most important things to realize about citizen's arrest is, law enforcement in the United States really wishes you wouldn't do it. It's the stock line they feed reporters every time they're asked about the latest "Homeowner Take the Law Into His Own Hands" story on the local news: "It's legal, but we don't recommend it." You see a variation on that line in reports from Indiana, Oregon, California, Iowa, and Texas, just to name a few states. Police don't actively encourage making a citizen's arrest, but they also don't forbid it, because it is, generally speaking, a legal act. But what's legal and what's not depends on where you live...
Laws Vary State-to-State
While the police would rather you call 911 and leave the dangerous and legally fraught job of arresting people to them, it's legal in most states to conduct some form of citizen's arrest or "detention" of a suspect. If you're the kind of person who imagines themselves one day making a citizen's arrest, do yourself a favor and use the comically large search bar over at www.usa.gov to research citizen's arrest laws in your state. It might save you a mountain of legal fees, or even from being prosecuted after bungling the job.
It's Best If You've Actually Seen a Crime Happen
It sounds obvious, but your best bet for a legit citizen's arrest is to take action after witnessing a crime, even if state law doesn't require you to do so. It's legal in many states to make a citizen's arrest for felonies you didn't witness. In California, for example, Penal Code Section 837 says "a private person may arrest another: (1) For a public offense committed or attempted in his presence" but also "(2) When the person arrested has committed a felony, although not in his presence."
Fifteen other states replicate California's law on this matter, while others vary slightly. Some are far more strict: in New York, for example, you will likely be liable for false arrest unless you actually see a felony occur. Private security firm owner Jeromy McHenry, who has made more than 1,000 citizen’s arrests, told the New York Times he always tells his new trainees, “If you didn’t see it, it didn’t happen.”
Don't Mess Around With Misdemeanors
The allure of making a citizen's arrest to stop a felony such as a murder is undoubtedly strong. It's an understandable urge. (It's also extraordinarily dangerous and not recommended by police.) But using your legal right to perform a citizen's arrest to stop a misdemeanor from happening? That's tricky territory. Your state might not allow you to do so (Michigan doesn't), and if it does, it the crime may need to qualify as a breach of peace.
Whether or not a crime qualifies as a breach of peace isn't always cut-and-dry: an appellate court in Texas decided driving while intoxicated isn't necessarily a breach of peace; it depends on the degree to which the driving was erratic and dangerous. This means a private citizen pulling over and arresting a drunk driver in Texas may be liable for false arrest or imprisonment, even if the driver is, in fact, highly intoxicated.