My lovely wife sent me a link to the PistolCam. It's a small camera that fits on pistol accessory rails and works like to a tactical light, taking pictures of whatever the gun is pointed at once it leaves the holster.
Frankly, I'd really like to see this sort of technology applied more widely to police work. I cannot think of any reason why SWAT teams can't have a small video camera on their helmets and microphones mounted to their gear. The equipment could be put together cheaply (<$1000), could be lightweight, and would provide invaluable evidence if anything goes wrong in a raid. It would exonerate the good cops and condemn the bad ones. Just what citizens want.