Suspension or Expelled from School Rules

I am now Highly Suspicious that at My sons School something very odd is going on.In brief a few people including him have been and are being bullied by the same culprits.They have been identified and basically their only sanction after numerous complaints even after suicide was mentioned by one of the pupils.is detentions by sitting at a desk.It seems apparent to me that they obviously don't realise the consequences of their actions.But more than this,I question whether the fact that the school hasn't expelled or even suspended them could have something to do with it's affect on the school tables or budget in same way?.Im not quite sure how these things work but to me it just seems common sense that if a teenager has repetitive negative behaviour then you have to send out a clear message if the 1st and 2nd hasn't hit home AND if others are suffering as a consequence.Because young lives could be lost