The first thing you should do when you go to court is to ask the judge whether your friend pleads guilty or not. If he pleads guilty, there is nothing to do. Please plead for yourself and say how pitiful he is. The more pathetic you are, the better! If you don't plead guilty, apply for legal aid. A lawyer will defend your friend. It seems that more than 400 Hong Kong dollars is free.
To be honest, if the signature is fake, I suggest your friend plead guilty immediately and seek leniency. Otherwise, if you lose the case, you will be sentenced to a heavy penalty.
False signatures are a crime of using false documents. When a criminal case comes, the sentencing point is between 5 years and 20 years. It depends on the judge. It’s best to be mentally prepared!!!!