Last year in Norristown, Pa., Lakisha Briggs' boyfriend physically assaulted her, and the police arrested him. But in a cruel turn of events, a police officer then told Ms. Briggs, "You are on three strikes. We're gonna have your landlord evict you."

Yes, that's right. The police threatened Ms. Briggs with eviction because she had received their assistance for domestic violence. Under Norristown's "disorderly behavior ordinance," the city penalizes landlords and tenants when the police respond to three instances of "disorderly behavior" within a four-month period. The ordinance specifically includes "domestic disturbances" as disorderly behavior that triggers enforcement of the law.

After her first "strike," Ms. Briggs was terrified of calling the police. She did not want to do anything to risk losing her home. So even when her now ex-boyfriend attacked her with a brick, she did not call. And later, when he stabbed her in the neck, she was still too afraid to reach out. But both times, someone else did call the police. Based on these "strikes," the city pressured her landlord to evict. After a housing court refused to order an eviction, the city said it planned to condemn the property and forcibly remove Ms. Briggs from her home. The ACLU intervened, and the city did not carry out its threats, and even agreed to repeal the ordinance. But just two weeks later, Norristown quietly passed a virtually identical ordinance that imposes fines on landlords unless they evict tenants who obtain police assistance, including for domestic violence.

Today, the ACLU, the ACLU of Pennsylvania, and the law firm Pepper Hamilton filed a federal lawsuit on behalf of Ms. Briggs, challenging the ordinance. These laws violate tenants' First Amendment right to petition their government, which includes the right to contact law enforcement. They also violate the federal Violence Against Women Act, which protects many domestic violence victims from eviction based on the crimes committed against them, and the Fair Housing Act, which prohibits discrimination based on sex, and was enacted 45 years ago this month. The ACLU has long argued that evictions based on domestic violence can discriminate against women, because such evictions are often motivated by gender stereotypes that hold victims responsible for the abuse they experience, and because the vast majority of victims are women.

Norristown is not alone. Cities and towns across the United States have similar laws, sometimes referred to as "nuisance ordinances" or "crime-free ordinances." We represented a domestic violence victim in Illinois, who after years of experiencing abuse, decided to reach out to the police for the first time. The police charged her husband with domestic battery and resisting arrest. Yet only a few days later, the police department sent her landlord a notice, instructing the landlord to evict the victim under the local ordinance based on the arrest. The message was clear: calling the police leads to homelessness.

A recent study of Milwaukee's nuisance ordinance showed that domestic violence was the third most common reason that police issued a nuisance citation, far above drug, property damage, or trespassing offenses. The study also established that enforcement of the ordinance disproportionately targeted African-American neighborhoods. The result? Women of color, like Ms. Briggs, were less able to access police protection.

Effective law enforcement depends on strong relationships between police and members of the community. These ordinances undermine that trust, by punishing victims who call 911 and coercing them to endure escalating violence in silence. Even worse, Norristown reports that domestic violence victims make up 20 percent of its homeless population. In order to reduce domestic violence and homelessness, Norristown should repeal the ordinance, and keep it off the books for good. And other towns that are considering enacting or enforcing these ordinances should learn the same lesson.

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