IMO:
This looks a bit too well thought-out to be an emotional outburst (eg: from a girlfriend/spouse). Also, I am guessing it would take some force to pierce the bonets with a pick. I reckon it is more likely to have been a guy pissed off with his boss.
Then again it could be a woman's car (something we haven't considered), with an emotional outburst from the husband/boyfriend/toyboy ??
