Last January, a woman in Lakewood, Ohio, ran to her neighbor’s house, bleeding from her face with a broken nose and concussion from a vicious attack by her boyfriend. With her neighbor’s help, she called the police, who took her to the hospital. Three days later, the city wrote the woman’s landlord: “Your tenant had a visitor over to the residence where he assaulted her. He was charged with felonious assault. This activity qualifies the property as a nuisance.”

A few months earlier, another Lakewood resident called a suicide hotline and threatened to kill himself. The crisis center alerted local police, who then sent a letter to the man’s landlord. “This activity qualifies the property as a nuisance,” a city lawyer warned, also noting that the man had been attacked by a stranger a few months earlier and had an unrelated argument with a friend. “You can avoid being charged the costs of abatement by taking documented steps to prevent any further nuisance activity.” Within weeks, the property owner evicted the “nuisance” tenant.

In both cases, tenants placed calls that may have saved their lives. But under local laws known as criminal activity nuisance ordinances, these calls also placed them at risk of losing their homes. Thousands of cities nationwide declare properties a “nuisance” if police or emergency services respond to an address too frequently, which typically means more than once within a year. Property owners face fines of hundreds or thousands of dollars, or even misdemeanor criminal charges, if they do not address the nuisance, which often means evicting the people who live there. A study of Milwaukee landlords found that eviction of tenants was the most common response to nuisance letters.

Proponents argue these laws create safer communities by giving cities tools to get rid of burdensome residents without the proof or process necessary to convict someone of a crime. Working with colleagues at Cleveland State University and the American Civil Liberties Union of Ohio to collect and analyze thousands of pages of nuisance-related public records, we discovered a disturbing trend in the enforcement of these laws: Nuisance designations are regularly given to properties occupied by survivors of domestic violence, people experiencing mental health crises and residents seeking medical assistance to prevent a fatal drug overdose. Even nonprofit organizations serving people with disabilities face nuisance fines when the people they serve require medical attention.