I've often thought about sticking my GP on the dash of my rig for work. Just for the same reasons,.. Those Idiots on the road who on a daily basis keep attempting to use my truck to commit suicide on/under/with. The reality is, it is a lot of inconvenience for me to always remember to keep it in my work bag, have fully charged, deal with dl'ing or purge the days recordings off the memory card, mount, unmount it, etc. etc. etc!!
Of course, it would definitely be worth it and justify all the hassle the one time it clears me of someone elses stupidity. (...just remember, it cuts both ways. You will have a record the first time you
make a mistake as well!)