This mistrust often leaves many black communities in a bind. As a recent poll by National Public Radio found, African Americans cite crime as their primary concern - and at the same time give police low marks.
"It's a thorny issue," said Nancy La Vigne, director of the Justice Policy Center at the Urban Institute in Washington.
"On one hand, you have people telling police, 'I'm scared to go to the convenience store; I can't leave my house without fear of getting shot. We want you here.'
"On the other hand, residents are saying, 'We feel under siege by police. You are making us guilty by association, because of our race, the color of our skin.' "
There has to be a better way to improve public safety without engaging in massive, racially targeted violations of the Fourth Amendment.
Washington Police Chief Cathy Lanier thinks she's found it. In the District of Columbia, police have made roughly 2,000 stops a year since 2010. During that time, she said, there have been only 20 complaints from motorists.
"I am not a fan of zero-tolerance policing," Lanier said. "When you have all your officers stopping and arresting citizens for minor violations, you don't have anybody left to go after the real crooks, and then it looks like police are in cahoots with the criminals."
As for the argument that black neighborhoods are targeted by police because that's where most of the violent offenders commit their crimes, she said:
"Those same neighborhoods also have most of the victims and witnesses. To solve and prevent crime, we must have their trust and cooperation."
It's time for other law enforcement agencies to follow her lead.
I'd been detained for making what the law calls "furtive movements."
That means I appeared to be up to something - at least to one bifocal-eyed tourist.
Milloy is a columnist for The Washington Post.