Cameras. Every human in any official position of authority of force should be required by law to wear a camera that records at all times video and audio. If the camera ever is disabled for any reason, their testimony for those periods should be considered invalid. The videos recorded should be considered part of the public record.[1]
Law enforcement works for the people, not the other way around. Many need to be reminded of that fact.
[1] Obviously in certain cases this is not desirable; e.g. sting operations. Modern technology is at the point that all faces in a video can be automatically blurred. Individuals who wish their face to be unblurred could specifically request so.
