You can call the police on your roommate’s guest when that guest is committing a crime, making credible threats, violating noise laws, or refusing to leave after being clearly told to go. Outside those situations, officers will usually treat it as a civil dispute and leave without doing anything. Knowing which side of that line you’re on matters, because a call made at the wrong moment can put your housing, your finances, and occasionally your freedom at risk.
When a Call Is Justified
Police respond to crimes and immediate safety threats. If your roommate’s guest is dealing drugs in the living room, stealing your property, breaking things, or physically assaulting someone, 911 or your local non-emergency line is the right call. The same applies to credible threats of violence. A guest who brandishes a weapon, corners you, or makes specific threats has crossed from annoyance into criminal territory, and officers will treat it that way.
Noise complaints also count, depending on local ordinances. If a guest is throwing a party at 3 a.m. and your roommate won’t intervene, a noise call is a legitimate use of police resources. Officers may issue a warning or a citation.
A useful test: if a stranger on the street did the same thing, would you call the police? If the answer is yes, the fact that it’s happening in your apartment doesn’t change anything.
When Police Will Not Get Involved
If the guest is simply annoying, overstaying, or making you uncomfortable without breaking any law, officers will almost always tell you it’s a civil matter. They’ll show up, confirm no crime is in progress, and leave. Police are not mediators for roommate disagreements, and they have no authority to remove someone just because you want them gone.
That is especially true when your roommate invited the guest and wants them there. Both tenants on a lease generally have equal rights to use the shared space, including the right to have visitors. Courts have consistently held that one co-tenant cannot unilaterally revoke another co-tenant’s right to invite guests. As long as one leaseholder has given the guest permission to be there, the guest is not trespassing, and your objection does not override your roommate’s invitation.
Officers know this. From their perspective, the guest has lawful permission from someone with the right to grant it, and your disagreement with your roommate is a private dispute. Expect them to suggest you work it out yourselves.
Turning a Guest Into a Trespasser
If you’re the only tenant on the lease, or your roommate also wants the guest gone, you’re on stronger footing. A guest who refuses to leave after being clearly asked can be treated as a trespasser. The process matters, though. Police responding to a trespass call want to see evidence that the guest was told to leave and refused.
Written notice is the strongest approach. A short statement revoking permission for the person to be in your home, with a specific date by which they need to leave, gives you documentation if you need to call police later. A text message works. Keep a copy. Officers are far more likely to act on a clear paper trail than on a he-said-she-said at the door.
Even with documentation, police may hesitate. If the guest claims they live there or that another tenant gave them permission, officers sometimes decline to make that call on the spot and tell you a court needs to sort it out. That’s frustrating, but police who forcibly remove someone with any colorable claim to residency risk liability of their own.
The Nuisance Ordinance Trap
Here is the risk most people never hear about until it’s too late. Hundreds of municipalities have nuisance ordinances that classify a property as a “nuisance” based on the number of police calls made to the address. Once your building hits the threshold, the landlord faces fines, potential loss of their rental license, or other penalties. The landlord’s predictable response is to evict the tenant associated with the calls.
Many of these ordinances don’t distinguish between the person causing the problem and the person reporting it. If you call police three times about your roommate’s threatening guest, all three calls count against your address regardless of fault. Some ordinances have been applied even when the tenant was the victim of the conduct that prompted the call. Domestic violence situations are especially affected: a tenant who calls because a guest assaulted them can end up facing eviction because the address accumulated too many police contacts.
For a genuine emergency, always call. For a situation that is disruptive without being dangerous, it is worth knowing whether your city or county has a nuisance ordinance and where the trigger sits before you dial.
Drugs and Constructive Possession
One scenario deserves its own warning. If your roommate’s guest brings illegal drugs into your shared living space, you could face criminal charges even if the drugs aren’t yours. Under the doctrine of constructive possession, prosecutors can argue that anyone with knowledge of and access to drugs in a shared area had control over them. The factors that matter are whether you knew the drugs were there, whether you had access to the space where they were found, and whether you had any apparent ability to control what happened to them.
If police raid the apartment and find a guest’s stash in the common area, everyone present could potentially be charged. The risk is highest when drugs are in plain view or in spaces you clearly use. If you become aware that a guest is bringing drugs into your home, the safest move is to report it yourself, document that you objected, and physically distance yourself from the situation. Waiting it out is the worst option.
False Reports
Before you call, make sure you’re reporting something real. Filing a false police report is a crime in every state. Minor false reports are typically charged as misdemeanors with fines and up to a year in jail. If the false report involves a serious allegation or leads to someone being hurt during the police response, charges can escalate to a felony with steeper penalties.
The collateral damage is worse. A false report destroys your credibility, so a later legitimate complaint about the same guest gets taken less seriously. The person you falsely accused may also have grounds to sue you for defamation or malicious prosecution. Exaggerating annoying behavior to make it sound criminal is a gamble with your own freedom and finances.
Better Options When the Guest Is Not a Criminal
When the problem is real but not criminal, you have routes that don’t run through 911.
Your Landlord
For many guest disputes, the landlord is a more effective first call than police. Landlords have a financial stake in lease compliance, and they have tools officers don’t. If a guest’s behavior violates specific lease terms — exceeding permitted occupants, staying beyond an allowed duration, causing property damage — the landlord can issue a notice to cure or quit, typically giving three to ten days to fix the violation or face eviction proceedings.
Landlords aren’t mediators for personality conflicts. “I don’t like my roommate’s boyfriend” goes nowhere. “My roommate’s boyfriend has been staying here for three weeks straight in violation of the seven-day guest policy” is a different conversation.
Small Claims and Protective Orders
If a guest damaged your property, small claims court can recover the cost. Filing fees vary by jurisdiction, generally between about $15 and $400. Bring photographs, repair estimates or receipts, and any messages exchanged with the guest about the incident.
For harassment or repeated threatening behavior, you can petition a court for a restraining order or protective order. The standard generally requires showing that the behavior would cause a reasonable person to feel afraid or harassed. You don’t necessarily need to have been physically harmed; a credible pattern of threats, intimidation, or stalking can be enough. The specific order available depends on your relationship to the person, since some orders are limited to family or household members and others cover broader civil harassment. Once issued, an order gives police something they otherwise lack: a clear basis to arrest on the next visit.
When a Guest Has Become a Tenant
One boundary worth naming. A guest who stays long enough can gain legal status as a tenant or occupant, even without paying rent and even without being on the lease. Once that happens, calling police won’t work. You’ll need a formal eviction, which can take weeks or months.
Thresholds vary. Some leases treat unauthorized occupancy as more than seven consecutive nights or fourteen total nights within a set period. Local laws set their own benchmarks. Signs a guest has crossed the line include receiving mail at your address, keeping most of their belongings there, staying overnight regularly for weeks, or having no other residence. If any of that applies, be careful. Self-help eviction (changing the locks, putting their things outside, cutting off utilities) is illegal in nearly every state and can expose you to serious financial liability, including orders to let the person back in, temporary housing costs, lost property, and in some cases punitive damages. Talk to a local tenant’s rights organization or attorney before acting. A consultation costs far less than a wrongful eviction judgment.