Wow.  I can imagine being in that man's shoes.  It sounds as if his son could have been more disturbed than originally thought at the other arrest.  I would be devastated if I felt so threatened by my own child that I had to resort to violence.  I mean, how terrible it must be!  Though details aren't completely clear, it sounds as if the son had some issues that weren't completely dealt with and it resulted in some sort of confrontation with his dad.  How terrible to have to carry this with him the rest of forever.  It would break my heart in two.  I hope he gets deep counseling for his grief and guilt.  Perhaps if the son had, it wouldn't have happened.  More's the pity.