I'm a criminal defence barrister. I can help.
Tell me exactly what you told the police? Did you have a lawyer at the police station?
Hmm... you might have some problems. I say this because provocation is not a defence. Are you sure you cannot say that you feared for your safety and were acting in self-defence?
S.20 is quite serious, it is grievous bodily harm without intent (s.18 is with intent, so alot more serious). If you have a trial it will be dealt with in the crown court. What are the injuries?
The guidelines (page 7) will give you a sentence indication (dowload the definitive sentencing guidelines, easy to find on google).
Even if you're found guilty I very much doubt you will go to prison as you have no previous convictions. I say this because if you do get a prison sentence I am strongly of the view it would be suspended (you only go to prison if you commit another offence within the period of suspension).
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