Some big cities give rebates for security cameras

Washington, D.C., Philadelphia, and Chicago all offer residents compensation for installing security cameras if the residents register the cameras with police. 

The idea is to increase the availability of video evidence for police investigating crimes.

The police can only access video footage with permission from the camera owner. If the camera owner refuses, the police can ask a judge for a warrant.

Washington, D.C. offers up to $200 per camera.

Supporters of the program argue that the presence of surveillance cameras can reduce crime. One study found that cameras in parking lots can decrease crime by half. 

Opponents of the program point to other evidence that cameras do not reduce crime, or simply move crime to disadvantaged neighborhoods that cannot afford cameras. There are also concerns that widespread camera surveillance infringes on privacy rights.