In any walk of life suspending someone on full pay pending an investigation is common. Its essentially saying you're innocent until proven guilty, whilst acknowledging there is an issue that is deemed serious enough to suspend someone from their job.
He's brought his employer into disrepute. I worked with a guy who got sacked after being convicted of drink driving. No jail term, but it was in the local rag, named his employer and they sacked him.
The main issue i guess is not that he defended himself from a guy with a bottle, its that he continued punching him when he was down and unarmed and then again when he got up. Hales, if he did put the boot in, has a problem as well.