Can the identity certificate of the victim and the testimony of the parties in the affray case be used as evidence?

There are 10 people on the other side. This case should be easy to investigate. The police only need to break through two people on the other side. The transcripts of the two people you have can basically convict. Hitter 16 years old, eligible for bail. According to the law, if you can't find the principal offender in the end, your losses will be compensated by all participants of the other party.