All drivers commit traffic violations. But most do not know that, according to the Supreme Court, the police can arrest them even for the most minor infractions, like failure to wear a seat belt. The traffic violation that most commonly lands a driver in jail is driving with a suspended license, which usually results from failing to pay a ticket.

Recent reporting on the topic has sparked discussion over how such arrests are disproportionately concentrated in poor communities, essentially punishing people for being too poor to pay. Compounding their financial problems, many of those arrested can ill afford the snowball effect of overdue fines, court appearances and, potentially, jail time. This has become an all-too-familiar pattern in how the criminal justice system exacerbates inequality.

The history of how we got to this point begins in the early 20th century with the opposite situation: the arrests of the automobile’s early adopters, people with social and economic standing. Though not all were wealthy — by the mid-1920s, a majority of American families owned a car — they were largely white and deemed respectable.

The traffic ticket system actually developed to replace arrests as part of an effort to foster better relationships between these citizens and the police. But it has now transformed into a policy that undermines equality and further erodes poor and minority Americans’ trust in the police.