In both Britain and the US, when a person is accused of a rime it must be shown that they are guilty "beyond reasonable doubt". A person is always innocent(无罪) in the eyes of the law until they have been proved to be guilty by a court they can sometimes ask for permission to APPEAL(上诉) to a higher court in the hope that it will change this decision.
Criminal law in England and Wales
When someone is arrested (ARREST) by the police, a MAGISTRATE (=an official who judges cases in some types of courts) decides whether there is enough EVIDENCE(证据) against the person for the case to go to court. If there is enough evidence and the case is a serious one, the person accused(控告) of the crime (called 'the accused(被告)') is sent to a CROWN COURT for a TRIAL with a JUDGE and JURY (=12 members of the public who have to decide if the accused is guilty(有罪的), then the judge decides the SENTENCE(判决) (2) (=punishment). If there is enough evidence against the accused but the crime is not a serious one (for example a traffic offence) then the case is heard in a MAGISTRATES COURT.