Lyric discussion by HeySka 

Cover art for A Sad Silence lyrics by Mighty Mighty Bosstones, The

To me is sounds like it's about some kid who acts like a tough guy, and is constantly beating up on this other kid. Unfortunately no one ever does anything to stop it and one day the tough guys kills the other kid.

So going with that it seems to me to be about how violence in the youth needs to stop.