Michael Brown’s family said police should adopt body cameras. They’re right.

Following the grand jury’s decision not to indict Ferguson, Missouri, police officer Darren Wilson for the shooting of Michael Brown, the Brown family called for police across the country to adopt the use of body-worn cameras.

There’s a good reason police cameras are getting so much attention: if police officers were required to wear body cameras questions about their conduct — like the ones that have arisen in the wake of the Brown shooting — could be entirely avoided.

The devices are small cameras that can be attached to a police officer’s uniform or sunglasses or worn as a headset. Such a camera could have fully captured the entire confrontation between Brown, an 18-year-old black man who was unarmed at the time of the shooting, and Wilson.

But without the cameras, the public is left with conflicting accounts from police and eyewitnesses about what, exactly, happened. Police insist Brown was confrontational throughout the encounter, while publicly known eyewitnesses say Brown was actually trying to surrender before he was shot and killed.

The police car around which the incident took place wasn’t equipped with a dashboard camera, which could have also provided some hints about what happened. But even that wouldn’t have given the full story, since most of the incident took place beyond the field of view of any potential dash cam.

At least some officials involved in Ferguson support body cameras. Missouri Highway Patrol Captain Ron Johnson, whose department Gov. Jay Nixon put in charge of security in the St. Louis suburb, spoke favorably of the concept at a press conference on Friday. “I believe in cameras,” he said.

Jay Stanley, a senior policy analyst at the American Civil Liberties Union who’s written about body cameras, says the cameras could benefit both the public and police by avoiding he-says-she-says situations and deterring police abuse.

“They have the potential to be a win-win situation,” Stanley says. “A lot of departments are finding that for every time they’re used to record an abusive officer, there are other times where they save an officer from a false accusation of abuse or unprofessional behavior.”

Stanley argues that the cameras are worth the cost and could actually save police departments money by protecting them against lawsuits. “In an era when police are obtaining very expensive, high-tech military weaponry that they don’t need, it’s silly to argue that this important technology that can serve as an important check in society on frequently abused police power shouldn’t be a priority,” he says. “The cost of one expensive citizen lawsuit against police can pay for a lot of cameras.”

There are also some concerns about privacy and whether police should be able to record just anyone and anything they encounter, particularly in instances when an officer goes inside another person’s home.

In the ACLU report, Stanley outlines the types of body camera policies that could protect people’s privacy: police officers could be required to disclose to people when they’re being recorded, and the recordings shouldn’t be kept for more than a few weeks if the data isn’t relevant to an investigation.

A big problem is these policies could, if they’re tailored poorly, allow police to turn off body cameras during situations that would require the recording to solve a case. These types of poor policies would essentially put the issue back to square one, with conflicting accounts acting as the only evidence.

Still, with a body camera and proper policies, it would be clear whether Brown really physically assaulted an officer before he was shot, whether Brown reached for the officer’s gun, and whether Brown tried to surrender before Wilson killed him. The question for public officials is if knowing all of that information is worth the costs.

To learn more about body cameras, read Vox’s full explainer and watch the video at the top of this page.