Under Thai Law, the plaintiff must bring a civil case to the court where the cause of action arises or where the defendant is domiciled. Where an immovable property is involved, the plaintiff has to bring a law suit to the court where such property is situated, or where the defendant is domiciled. However, in the consumer case, in which the business operator will bring a case against the consumer, only domicile principle is applied.
In Bangkok, Courts of First Instance dealing with civil cases are the Civil Court, the Bangkok South Civil Court, the Thon Buri Civil Court, the Min Buri Civil Court, the Taling Chan Civil Court, and the Phra Khanong Civil Court, depending on the district where the cause of action arises or where the defendant is domiciled.
For disputes on civil matters occurring outside the territorial jurisdiction, the Civil Court has discretion either to try and adjudicate those cases or to transfer them to the court having territorial jurisdiction.
As regards criminal cases, the court in a district where an offence has been committed, alleged or believed to have been committed, or where an accused resides or is arrested, or where and inquiry official makes an inquiry has jurisdiction over the cases. In Bangkok, Courts of First Instance handling criminal cases are the Criminal Court, the Bangkok South Criminal Court, the Thon Buri Criminal Court and the Min Buri Criminal Court, the Taling Chan Criminal Court, and the Phra Khanong Criminal Court, depending on the district where an offence has been committed, alleged or believed to have been committed, or where an accused resides or is arrested, or where an inquiry official makes an inquiry. Like the Civil Court, the reason to establish other criminal courts in Bangkok was to alleviate the workloads of the Criminal Court. Also, the Criminal Court has a discretion either to try and adjudicate criminal cases arising outside its territorial jurisdiction but was brought before it or to transfer to the court having territorial jurisdiction.
Provincial Courts exercise unlimited original jurisdiction in all general civil and criminal matters within their own districts which are generally the provinces themselves. For the purpose of expansion of services of the court to the distance area, some provinces of the court to the distance area, some provinces may have more than one Provincial Court. For example, in Nakhon Ratchasima Province, there are three Provincial Courts, i.e., the Nakhon Ratchasima Provincial Court, the Sikhio Provincial Court and the Bua Yai Provincial Court. Where a case within the jurisdiction of the Municipal Court is brought to the Provincial Court, the latter has to transfer the case to the former.
Each Provincial Court has a Chief Judge who is the head and responsible for the judicial work of the Court. The Director of “The Administrative Office of such Provincial Court under the supervision of the Chief Judge is responsible for administrative work of the Court”
The Municipal Court is known as Kwaeng Court. There are six Municipal Courts in Bangkok Metropolis : the Bangkok North Municipal Court, the Bangkok South Municipal Court, the Thon Buri Municipal Court, the Dusit Municipal Court, the Pathumwan Municipal Court and the Don Muang Municipal Court. The primary function of Municipal Courts is to dispose of small cases quickly with minimum formality and expense. The jurisdiction of these courts covers both criminal and civil cases. Criminal cases fallen in the jurisdiction must deal with the criminal offence punishable with a maximum of three years imprisonment, or fine not exceeding 60,000 baht or both. For civil cases, the amount of claims must not exceed 300,000 baht. The proceeding in Municipal Courts is emphasized on the speedy trial; therefore, the trial is more simple and oral judgment or summarized judgment may be issued.