A landlord can’t evict a tenant just because a guest of the tenant brought drugs onto the property, according to an appeals court in Tennessee.

The tenant, a single mother, had invited three friends over to watch videos and spend the night. During the night, police investigated a nearby burglary asked permission to enter and search the apartment. They discovered that one of the guests had placed a small amount of marijuana under a sofa cushion.

The tenant herself had no knowledge of the marijuana, and had specifically prohibited guests from bringing drugs into her apartment. Nevertheless, the landlord announced that it planned to evict her. She sued.

The apartment lease said that the landlord could evict the tenant if there were a single instance of “drug-related criminal activity” in the apartment, even if it was committed by a guest. But the court said this simply wasn’t fair, and the landlord couldn’t evict the tenant unless the tenant at least knew about the drugs.

The lease also said that the tenant could be evicted if there were “a real and present danger to the health, safety or welfare of…other tenants or persons on the premises.” But the court said that the presence of a small amount of marijuana wasn’t “a real and present danger” to anyone’s health or safety.

However, courts in other states have decided otherwise, and a great deal depends on the facts and on the specific terms of the lease.