Kirk McConer was arrested and jailed while talking to a friend outside a convenience store, where he had just purchased a soda. Tyrone Hightower was arrested and jailed after sitting in his car in the parking lot of a nightclub, as he waited to make sure his friends were admitted to the club. And Jacob Manyong was stopped and placed under arrest after the back tire of his car barely crossed the property of a private business, as he drove out of an adjacent public lot.

The charges against McConer, Hightower, and Manyong? Trespassing.

Although the charges against each of them were eventually dropped, memories of the experience still linger—so much so that each of them remains fearful that he could be victimized again at any moment.

And they’re scared for good reason. Their respective ordeals were the product of a practice introduced by the Grand Rapids Police Department decades ago, which relies on the use of generalized “No Trespass Letters” to justify arrests for criminal trespassing on commercial property. But more to the point, the policy gives police in Michigan’s second-largest city an excuse to stop and search people immediately based on nothing more than a gut reaction to the way someone looks or acts—without bothering to determine whether the person is actually trespassing.

Here’s how it works: Grand Rapids police officers solicit business owners in select “high-crime” neighborhoods and ask them to sign a No Trespass Letter, stating that they do not want unauthorized people on their property and that they will cooperate with any efforts to prosecute trespassers. The signed letter, valid for one year, is then placed on file with the police department and can be renewed.

So far, so good, but here’s the rub:

According to Grand Rapids police officials, the signed letter allows officers to stop and arrest people for trespassing at the business in question—even while the business is open—whenever the officer thinks the person is on the property without a “legitimate business purpose.” In other words, cops are given unrestricted discretion to decide who does and does not belong on the property of an open business, without ever talking to the business owner or any employee to find out why the person is on the property, how long they’ve been there, and whether the person is welcome on the premises.

Which raises the question: How can Grand Rapids patrol officers possibly know who is and is not a trespasser without first determining whether the business has authorized the person to be there?

The short answer is: They can’t. But if the business has a No Trespass Letter on file, police officers are given carte blanche to make that very judgment.