I was on a bus with a friend today.

The bus was packed & the only two seats available were one at the back & one at the front. I sat on the back seat & my friend sat at the front. I passed the journey by gazing out of the window & didn't pay much attention to the rest of the passengers.

Suddenly, totally out of the blue, my friend jumps out of his chair, grabs some guy opposite him, picks him up & slams his head into the window. I ran to the front, my instinct being to back-up my mate. I had no idea what was going on at this time.

As I got to the front, my mate's got this guy by the neck & is about to punch him in the face. I stopped him, concerned he'd end up in the nick, by grabbing his free arm & asked him what he was doing.

People around us were backing away as best they could.

I looked at the guy he was about to hit & noticed immediately he was a retard, as he had that funny sort of face that retarded people have. I then noticed an ID badge of some sort hanging around his neck, identifying him as a mental patient from a local hospital.

Confused, I turned to my mate & asked him what the fuck he thought he was doing beating this bloke up. His reply was 'move, I'm going to banjo this bastard' (slang for kick the living shit out of him). I wasn't going to let him do that - the guy was a spastic - so started pushing my mate away. He then said, 'he's been looking up that girl's skirt'. As I looked at the girl, she was no older than about six & was holding onto her mother for dear life, while the mother herself was in tears.

As I'm pushing my mate away, the mother's saying 'thank you, thank you' over & over again to my mate. She was as distressed as it gets. My mate told me this guy had literally got on his hands & knees in front of the girl & lifted up her skirt for a look.

I was shocked. My immediate thought was to 'banjo' him myself, but as I turned to do so, he was grinning from ear to ear & obviously had no comprehension whatsoever of the danger he was in or what was about to happen to him.

Looking again at the girl & mother crying, the urge to beat the shit out of this guy returned, but when I turned back to do it, his gormless face made me realise he had no idea of what he had actually done.

If he knew it was wrong, he wouldn't have done it on a packed bus, would he?

At the end of the day, I threw the guy off the bus without touching him while holding my mate back at the same time. The mother was still spurting 'thank you' over & over & now my mate was angry at me.

Thinking about it now, I think I should have beat him up, but I couldn't bring myself to do it at the time.

I don't condone hitting mental people, but the way I see it, if I had given him a bit of a slap, he might have learned not to do it again, whereas now, he probably thinks he'll get away with it next time - when there might not be a bus full of people to stop him.

Should I have kicked the fuck out of the disabled guy, given him a bit of a slap, or did I do the right thing?

I have an awful feeling I did the wrong thing.