There's an app for that
A new smartphone app from the American Civil Liberties Union (ACLU) of New Jersey, called Police Tape, makes it easier to record law enforcement on your phone. The app, developed by OpenWatch and available for Android and iOS, disappears from the screen when you start recording, making it more difficult for cops to recognize that a recording exists on a phone they've seized. It also has an option to send a backup copy to the ACLU and includes legal information about what rights you have when interacting with cops.
Police Tape isn't the first app developed to combat police brutality. In August, in the wake of the shooting of Michael Brown in Ferguson, Missouri, three teenagers from Georgia developed an app called "Five O" that lets users document and rate their interactions with police. The New York Civil Liberties Union also recently released an app called Stop & Frisk Watch, which includes an alert if other users nearby are recording the police.