Standards for police are low enough. Supreme Court must stand against police retaliation.

It is hard to look into the faces of dozens of middle school and high school students and break their hearts. But the Supreme Court is forcing me to do it, and it may yet get worse.

I volunteer with a nonprofit organization, Street Law, which teaches young people about law, government and justice. Recently, I taught two such classes to students from disadvantaged public schools. The topic was criminal procedure, in which I explained some of the basic rights citizens have when encountering the police. This ought to be a basic civics class taught to all adolescents, and it is particularly important to teach to these mostly black and Latino children, who are likely to face hostile interactions with police.

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In my lesson, I used Jay-Z’s lyrics to the song “99 Problems," which engages them. The song describes an encounter with a police officer who pulls Jay-Z over for “doing 55 in a 54” zone. When the officer queries Jay-Z on why he pulled him over, the musician suggests, “ 'Cause I'm young and I'm black and my hat's real low?” When I asked the kids whether the police can do this, they universally respond, “No.”

It is my responsibility to tell them they are wrong.

All amendments are not created equal

They are right that under the 14th Amendment, such discriminatory practices are unlawful. But I have to explain that, under the Fourth Amendment, the Supreme Court has effectively allowed police to engage in racial profiling, as long as officers can point to some wrongdoing by their target, however minor, to use as cover.

Under the unanimously decided Whren v. United States, even if every car is driving over the speed limit, police can exercise their discretion as to whom to pull over, even if they choose on the basis of race, gender or any other what we would consider improper criteria. And this is true even though the court knows full well that it is practically impossible to follow every regulation concerning automobiles.

Suddenly, the schoolchildren have nothing to say. The middle schoolers just look hurt; the high schoolers look hurt and angry. I tell them I know it is unfair, and that they intimately understand this unfairness. After all, I do not know what it is to be a person of color living in America. They do.

The best I can do is tell them what they can do to help themselves. Like Jay-Z, who asks, “Am I under arrest or should I guess some more?”, the most important thing when stopped by police is to ask — politely — “Am I free to go?”

The conceit of this area of law is that people know when they are free to go, subject to a temporary stop, subject to a longer seizure or are under arrest, and the police do not need to clarify these stages. But, if asked directly, the police need to choose between admitting the person is not free to go, which clarifies the respective rights and duties involved in the encounter, or else letting the person go free. It is a small taking back of power, but it cheers up the children a little.

But the news could become worse for these students, depending on how the Supreme Court rules in a pending case, Nieves v. Bartlett.

Make it clear: Retaliation isn't right

The court is being asked to decide whether probable cause for a minor offense — be it driving 1 mile over the speed limit or failing to signal — not only allows the police to racially profile them, as Whren v. U.S. allows, but also to make a retaliatory arrest after a perceived slight or because of animus the officer may harbor.

In this case, respondent Russell Bartlett refused to talk to officers at a festival in Alaska. Later that day, Bartlett was arrested after he advised another festival attendee who appeared underage that he was free not to talk to the police. Bartlett alleges that an officer said, “Bet you wish you would have talked to me now." The officer denies that claim, and the charges against Bartlett were eventually dismissed.

To the Supreme Court, however, the state and federal governments argued that even if the officer explicitly revealed his animus, as long as the officer has probable cause of some wrongdoing, the right to free speech and the right not to talk to the police mean little in protecting yourself against retaliatory arrests.

The government even argued that it can discover some other offense at some later stage to use as cover if the original offense is not applicable.

I do not want to have to tell the schoolchildren next year that the police can brag that they are arresting them out of animus. I hope the Supreme Court saves me from having to apologize for adding that layer of unfairness to a system already stacked against them.

Tonja Jacobi is a professor of law at Northwestern Pritzker School of Law. Follow her on Twitter @TonjaJacobi.

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This article originally appeared on USA TODAY: Standards for police are low enough. Supreme Court must stand against police retaliation.