Activists raise their hands in solidarity as a policeman ties to block others, who were demanding justice for the shooting death of teen Michael Brown. (Adrees Latif/Reuters)

Charles Epp and Steven Maynard-Moody are professors at Kansas University’s School of Public Affairs and Administration. They are the co-authors, with Donald Haider-Markel, of “Pulled Over: How Police Stops Define Race and Citizenship.”

A recent Pew survey measured a vast gulf in how blacks and whites view the recent events in Ferguson, Mo. Eighty percent of blacks said that the shooting of Michael Brown, an unarmed, 18-year-old African American, “raises important issues about race that need to be discussed.” Only 37 percent of whites agreed. You might say that to blacks, whites just don’t get it.

After interviewing hundreds of drivers about their experiences in police stops, we can see why. African Americans experience not only more police stops than whites but also a completely different kind of stop. For many African Americans, the stop of Michael Brown on a Ferguson street was all too reminiscent of ones they have experienced themselves — stops they feared could spiral into violence. Many black men may now be saying, “There but for the grace of God go I.”

A thought experiment for white readers, drawn from actual examples from our interviews:

Suppose you are pulled over by a police officer while driving home from work. The officer doesn’t say you were speeding or ran a red light. Instead, he asks where you’re coming from and where you’re going. While you answer, he looks around your car with a flashlight. Then he lets you go, with no ticket or further explanation. Five minutes later, another officer stops you and asks the same questions, only to let you go again.

Or suppose you are standing in a yard, in an ordinary working-class neighborhood, talking to your friends. An officer drives down the street, stops and approaches with a hand on his gun. “Nobody move!” he barks. “Keep your hands where I can see them and show me your IDs.”

Or suppose you are driving home from school with friends and an officer pulls you over. He tells you that you look like the suspects in a recent burglary, then handcuffs you all and makes you sit on the sidewalk to wait for a witness to arrive to look at you. After an hour, he lets you go with no explanation.

Now suppose you’re black and that you’ve heard many stories like these from black friends and family members. How would you feel? We are confident it would be similar to the black drivers we interviewed: indignant, angry, even violated.

The incidents described above are called investigatory stops. Unlike traffic-safety stops, in which the purpose is to sanction safety violations, investigatory stops are intended to check whether a person is engaged in serious criminal activity. Our interviews revealed that while whites are quite familiar with traffic-safety stops, they have little experience with investigatory stops. But half of all stops reported by blacks were investigatory.

Investigatory stops can be tense, because people view them as unfair and fear what the officer may do next. They wonder: If an officer can handcuff me for an hour when all I did was drive through a white neighborhood, what is to prevent him from doing far worse? African Americans report that they try to prevent escalation by quietly putting up with the officer’s intrusions and teaching their children how to do the same. Police officers, too, recognize that these stops make people resentful and nervous, which in turn makes them edgy and poised to act forcefully to stay in control.

If we learned one bedrock lesson from our interviews, it is that African Americans fear that these tense, bitter interactions might spiral out of control into violence.

One black man told us he once asked an officer, “Why are you stopping me?” He said the officer responded by yelling, “Show me your hands, show me your hands.”

“He had his pistol pulled out,” the man reported, “and I didn’t even turn my head, but I could see it out of the peripheral vision of my eye, its barrel, and he pointed it right at my head. . . . That was pretty frightening.”

Police seek to justify investigatory stops as a way to fight crime proactively in high-crime areas, and it is true that these stops occasionally uncover illegal drugs and weapons. But this comes at a cost of stopping large numbers of innocent people. This “numbers game,” as police sometimes call it, sacrifices the dignity and trust of hundreds who are innocent to find one who is guilty.

There is a way forward: Rein in investigatory stops. African Americans resent not so much the police but a particular type of police activity. They, like whites, accept police stops made for a clear violation and not as a pretext to question and search. A black man who has been stopped many times told us, “If I’m at the wrong, you know, I could admit to it. If I’m clocked speeding, and I know I was speeding, I can accept that. But not when I’m harassed or, like I said, I’ve had a gun drawn at me for any particular reason and he wanted me to step out of the car, and raise my hands and all that.”

Ending investigatory stops would make it possible to begin rebuilding trust, stop by stop. Hiring more black police officers is essential but in itself will not address the problem. Even racially diverse departments such as New York’s have carried out far too many of these stops when this was the policy of police leadership.

The problem is not police stops — it is investigatory stops. These stops poison blacks’ attitudes toward the police — and toward the law itself. They undermine police effectiveness and turn the citizens of a democracy into the controlled — and resentful —subjects of a security state. It’s time to end them.