the description says
" The driver of the vehicle taping the video had a dash cam installed in his vehicle after being involved in a previous collision."
looks like he was pissed off about a previous collision and wishes he had a video to prove his side.
I keep one in my car so douchebag cops (no offense to non-douchebag cops) cant power trip or write another bullshit ticket. never got anything like this on tape before!