I should add that this is not necessarily an idea I am throwing out there that I want 'someone else' to do. I work on Flight Data Recorders as an Engineering/Technician for a living. I am great with hardware, but mediocre with SW (at least on a PC...assembly/machine language on micros-no problem.) I believe the SW involved is within my technical limits, and the hardware definitely is.
I had already thought of a name for the system (probably not original at all) which is 'iWitness.'
Finally, it is most important that the system is as anonymous as possible. This ensures the safety of the participants and subjects. Nobody should feel singled out or infringed upon enough to incite rage or legal proceedings. Of course, socio-politcal aspects of this are almost entirely dependent on the person publishing the results. Nothing you can do about that. However, the technology should take into consideration as much as possbile protections against the misuse -mistaken or otherwise.