Sorry, I hadn't realised that the SE23 forum required the same debating skills as the Oxford Union.
Without access to statistics, both our arguments come down to personal views. Yours seem to suggest that the majority of dogowners are irresponsible therefore we should make it tougher to own dogs. Mine are that I believe it's a minority of irresponsible owners and that it's harsh on the good owners to make their life difficult.
And yes, I could have picked on irresponsible lazy drivers, irresponsible cyclists, irresponsible litterlouts in my example but the expected reaction to using kids was well worth it.