Law of Thailand

The legal system of Thailand is a complex structure used to govern the nation and its people. It is primarily based on the civil law system. However, it has also been influenced by common law traditions. In a civil law system, written codes are the main source of rules. Common law is a system where past judicial decisions often guide current cases. Thailand uses both styles to manage different aspects of society.

Laws in Thailand follow a specific hierarchy to ensure order. At the very top is the Constitution of Thailand. This is the supreme law, meaning no other law can contradict it. The most recent version is the 2017 constitution. Below the constitution, the government uses Acts and statutes to create rules. These statutes often create or change the four basic codes: the Civil and Commercial Code, the Penal Code, the Civil Procedure Code, and the Criminal Procedure Code.

There are different ways laws are issued depending on the situation. For most things, the parliament passes laws. However, the King can issue an emergency decree or a royal proclamation. This happens when the cabinet advises that urgent action is needed. Such decrees might address national security, public safety, or economic stability. An example is the Emergency Decree on Public Administration in Emergency Situation BE 2548, issued in 2005.

Thailand's legal history shows how much the system has evolved. Before 1932, the area known as Siam did not have an uncodified constitution. In 1908, the King of Siam introduced a new penal code. He noted that ancient Siamese monarchs used laws derived from the Dhamasustra of Manu. This was a legal text originally used in India and neighboring countries. Over time, Thailand moved from these ancient traditions toward its modern legal structure.

Different branches of law handle specific parts of life. Public law includes constitutional law and criminal law. The Penal Code lists offenses that can lead to arrest or imprisonment. For example, the Narcotics Code BE 2564, effective in 2021, manages drug-related issues. It replaced several older laws to consolidate rules on manufacturing and use. This code is divided into three books: Prevention, Suppression, and Narcotics Control; Treatment and Social Rehabilitation; and Penalties.

Private law governs relationships between individuals and businesses. The Civil and Commercial Code is the most important reference here. It covers many topics, such as contracts, torts, and corporate law. A tort is a wrongful act that creates legal liability. The code also manages personal property and land law. Under the Land Code of 1954, land is categorized by different title deeds. One important type is the Chanote, which offers private ownership.

Intellectual property law protects new ideas and inventions. This includes patents, trademarks, and copyrights. The Department of Intellectual Property manages these matters. Thailand uses an "absolute novelty" and "first to file" system for patents. This means an invention must be completely new when the application is filed. There are three types of patents: invention patents, petty patents, and design patents.

Invention patents are granted to ideas that are novel and useful. They must also involve an "inventive step," meaning they are not obvious to experts. An invention patent provides exclusive rights for 20 years from the registration date. Petty patents are for inventions that do not require a major inventive step. These offer protection for 10 years. Interestingly, Thai law does not allow software to be patented. The law views computer software as a set of instructions rather than an invention. This has caused debates among economists and developers in Thailand.