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.
If found guilty in the Crown Court the accused may apply to（请求） the COURT OF APPEAL （Criminal Division） where he or she will be heard by a judge. Sometimes a HIGH COURT judge from the Queen's Bench Division assists in dealing with criminal matters in the Court of Appeal or Crown Court.
Criminal law in Northern Ireland
In Northern Ireland， as in England and Wales， someone accused of a crime may be tried in a Magistrates' Court or a Crown Court depending on how serious the crime is. Appeals from the Crown Court are heard in the Northern Ireland Court of Appeal.
Criminal law in Scotland
Scotland has a separate court system. After a person is arrested by the police， an official called the PROCURATOR FISCAL is in charge of deciding whether there is enough evidence against the accused for a trial. If there is enough evidence and the crime is a very serious one， the accused is sent to the HIGH COURT OF JUSTICIARY where there is a judge and jury（陪审团） （in Scotland there are 15 people on a jury）。 If there is enough evidence but the crime is a less serious one， the case is heard in a SHERIFF COURT （The sheriff is a trained lawyer who acts as a judge）。 Appeals from the Sheriff Court go to the High Court of Justiciary.
Criminal law in the US
The US has tow separate court systems. In general terms STATE COURTS are used when someone has done something against the laws of CONSTITUTION of a particular State. FEDERAL COURTS deal with cases to do with the laws and Constitution of the United States as whole. Federal courts also hear cases where the US Government is one of the sides involved（介入）。 Cases for crimes which are not serious are likely to be heard in state courts. Serious crimes may be tried in wither state courts of federal courts depending on the situation， for example cases where a crime has taken place in another state are often heard in federal courts.
After a person has been arrested a magistrate（地方官员）， or in some cases a GRAND JURY made up of between 16 and 23 citizens， decides whether they should go to trial. If there is enough evidence for a trial the accused goes to court and has to state whether he/she is guilty or not guilty of the crime. If they say they are not guilty they are sent to trial with a judge and jury （of 16 or 20 citizens） in either a State or COUNTY COURT or， in federal cases， a DISTRICT COURT. If the accused is found guilty they may have the fight to appeal to a higher court， as shown below.
The final court of appeal in the US federal system and for some cases in the state courts is the US SUPREME COURT. It is made up of a CHIEF JUSTICE and eight ASSOCIATES. The accused does not have the fight to be heard by the Supremes Court， but the Supreme Court decides which cases it will hear.