Absolutely. Furthermore - if you have the upper hand and can get away, then you are most likely committing a criminal offence by not doing so. The law doesn't r

Absolutely. Furthermore - if you have the upper hand and can get away, then you are most likely committing a criminal offence by not doing so. The law doesn't recognise the idea that you have the right to lay into someone for being an asshole, or even for breaking your nose. If you can get away and don't, then you are at risk of prosecution.