Ah man that is some bad bit of luck there! why have you not talked to him if you want know what happened. Or the police, they were the ones who made the decision of how they chose to react. Anything els is just guessing and speculation.
It's possible you suffer from trichotillomania. I had a friend in grade school who had this condition before it was understood.
From the Mayo Clinic: " Trichotillomania (trik-o-til-o-MAY-nee-uh) is a disorder that involves recurrent, irresistible urges to pull out hair from your scalp, eyebrows or other areas of your body, despite trying to stop."