This sub-thread was about speed cameras. I'd assume law enforcement agencies have some network they can hook the cameras up to. As for the drone in the video,

This sub-thread was about speed cameras. I'd assume law enforcement agencies have some network they can hook the cameras up to. As for the drone in the video, I wouldn't be surprised if there's a Raspberry Pi with a 4G modem, or some other remote networking option connected to it, somewhere inside it (or something of a similar hacky nature).