When there is an offence it absolutely has a sufferer. The first thing that sufferer should do urgently is report the police or sue to the court. When an officer realize about the case then he will investigate to find an offender.
When an offender is arrested, s/he call an accused. While arresting, the investigation officer will inform the allegations and the rights of the accused. During the investigation, the suspect will be in controlled for no more than 48 hours and staff will be required to prepare the case file to send to the public prosecutor to determine if the case is the grounds or enough evidence to convict the accused or to file a lawsuit.
If the prosecutor considers "Order not to sue", it means the cause and the evidence is not sufficient to the prosecution of the accused. But if the prosecutor "sues", it means that the evidence available in the investigation stage is enough to prosecute the accused.
When the government attorney submitted the case to the Court of First Instance that the court will consider the case to carry out of proceedings and make appointment date, inquire, investigate and judge the case.
If any parties – plaintiff (injured person) or defendant (alleged offender) – is not happy or refuses to admit with judgment of the Court of First Instance, he or she can appeal to the Court of Appeals. And if the plaintiff or the defendant is not happy with the Court of Appeals' judgement, they can be filed a petition to Supreme Court – the highest court.
The judgment of the Supreme Court is the final. If it appears that the defendant did not make a mistake as the government attorney sued, the court may have an order to release. But the judgment specified that the defendant is guilty, the court will specify penalty that the defendant to be received.
There are 5 levels of Criminal Penalty in Thailand – Confiscation of Property, Fine, Confinement, Prison sentence and Execution. If the defendant get an imprison sentence, he or she must be delivered to prison.
On the time to be punished that the prison have activities to assuage, recreate, solve behavior and practice occupation to prisoner. Some prisoners who behave well – help the prison job, do not brawl to be a good prisoner – may be released prematurely or break a penalty or reduce prison days.
Reference : Office of Justice Affairs pages