Police forces across the United States have come under scrutiny in recent weeks over their use of data from social media sites.

Last month, the American Civil Liberties Union revealed that several American law enforcement agencies were using bulk data from Twitter, Facebook and Instagram — gathered by a social media monitoring company called Geofeedia — to spy on Black Lives Matter activists in Ferguson and Baltimore.

Twitter and Facebook have since restricted Geofeedia's access to their data. But a group of activists from the Lucy Parsons Labs in Chicago are trying a different tactic to hold police accountable.

They're turning the tables on law enforcement by mining social media for information about the police and compiling that data in a crowd-sourced database called OpenOversight.

Jennifer Helsby, lead developer of OpenOversight, says they're taking a different approach to their data collection.

"We don't use the same firehose that the Geofeedia company did. We're just monitoring a few specific accounts, which anybody can do."

It's a police accountability tool designed to help Chicago residents who want to file complaints against police officers.

That's a real problem in Chicago, Helsby says. According to one study, nearly a third of the complaints against Chicago police between March 2011 and March 2015 were dropped because the officer couldn't be identified.

"I think citizens should be able to file complaints against police and have those complaints followed up on," she tells Day 6 host Brent Bambury.

U.S. police have come under scrutiny in recent weeks over their use of bulk social media data to surveil Americans. But a group of Chicago activists have turned the tables with 'OpenOversight,' a crowd-sourced web tool that mines social media for info. 9:12

The need for accountability

Helsby recalls an incident where a person said they were assaulted by an officer at a protest and tried to file a complaint. But while the complainant knew the race, gender and rough age of the officer, that wasn't enough. Because the officer's badge number or name was not provided, the oversight agency was unable to figure out who their officer was.

"They didn't get it as they were being beaten. As you could imagine, they didn't get out their notebook and write this down," she says.

According to Helsby, this is what sparked the idea for project.

"I think there's a general acceptance among citizens that local law enforcement shouldn't be anonymous. They're not a secret police force. They've got their names and badge numbers clearly displayed, because people recognize that there should be some accountability, and so this database is just providing a tool to help provide that accountability."

A screenshot from the OpenOversight database. Users can input information about a police officer — such as race, age or gender — and identify them via photograph to get the information they need to file a complaint. (OpenOversight/Lucy Parsons Lab)

Information in the database includes the name, badge number — information that would be displayed on uniforms — as well as a picture of the officer's face so that users can identify them.

In OpenOversight, users can input the race, gender and rough age of the officer in question. A panel of faces of policemen appears and they can click through until they have found one or a few that match their memory. At that point, they can proceed with their complaint.

Crowd-sourced database

According to Helsby, most of the information in their database comes from the police department itself.

"We file public records requests to get the names, badge numbers and demographic information for each officer, and then we use social media to get pictures of the officers from the police department's own Twitter accounts," she says.

They have also received submissions from activist groups. The website includes a form where people can upload photos they have taken of officers.

"We ensure accuracy by having volunteers look through every photo manually and make sure that the face and badge number are displayed, and then that's put into the database," she says.

CHICAGO, IL - December 24 : A demonstrator protesting the fatal police shooting of Laquan McDonald holds up a sign during an attempt to disrupt holiday shoppers along Michigan Avenue December 24, 2015 in Chicago, Illinois. Former Chicago police officer Jason Van Dyke, who was charged with murder last month in the shooting death of 17-year-old McDonald last year, was indicted on six counts of first-degree murder and one count of official misconduct last week. (Photo by Joshua Lott/Getty Images) (Getty Images)

Police concerns

Police representatives, including the Fraternal Order of Police, warn the database could potentially reveal the identities and jeopardize the safety of offices — particulary those who are undercover or working on an investigation.

But Helsby says the team behind OpenOversight is careful to ensure that does not happen.

"Any officer that is not walking around with their name and badge number displayed on the uniform in a public space doesn't make it into the database," she explains.

As the project is still in its early stages,there is no data yet showing that more complaints are being completed now because of the database.

"Our main goal right now is to get as many photos as possible from the communities so that we can have a rich dataset."

So far, they have received a contribution from one police officer. He sent them an email expressing his thoughts and concerns about the project, but said he realizes how important it is. He provided his own photo and updated his badge number because he had recently been promoted.

"He was very encouraging. That was really good to see," she says.

The next goal, Helsby says, is widespread adoption of this program.

She says they've already spoken with people in Toronto who have expressed interest in establishing a database for the city's police department.

"I would like to see other cities create similar tools. All of our code is online, so people can directly use what we've done."