Section 148 — Inquest for unnatural death
Statutory text (Thai original)
เมื่อปรากฏแน่ชัดหรือมีเหตุอันควรสงสัยว่าบุคคลใดตายโดยผิดธรรมชาติหรือตายในระหว่างอยู่ในความควบคุมของเจ้าพนักงาน ให้มีการชันสูตรพลิกศพ เว้นแต่ตายโดยการประหารชีวิตตามกฎหมาย การตายโดยผิดธรรมชาตินั้นคือ
(๑) ฆ่าตัวตาย
(๒) ถูกผู้อื่นทำให้ตาย
(๓) ถูกสัตว์ทำร้ายตาย
(๔) ตายโดยอุบัติเหตุ
(๕) ตายโดยยังมิปรากฏเหตุ
English translation
When it clearly appears, or there is reasonable ground to suspect, that a person has died by unnatural cause or died while in the custody of an official, an inquest shall be held, except death by execution according to law. Unnatural death means:
(1) suicide;
(2) being killed by another person;
(3) being killed by an animal;
(4) death by accident;
(5) death by a cause yet unascertained.
This English translation is provided for reference only and has not yet been firm-verified — always rely on the Thai original.
Firm annotation
This section opens Chapter 2 on inquests and sets the trigger for holding one, defining unnatural death exhaustively in five categories and expressly capturing deaths in official custody. It is the gateway to the inquest machinery in sections 149 to 156, which allocate duties to report, examine, and, in custodial or duty-related deaths, hold a court inquiry. The only carve-out is a lawful execution. The inquest is part of the investigative process, so its purpose is to establish the details and cause of death rather than to decide guilt.
Why this matters in practice
For a bereaved family, this section is what obliges the authorities to investigate an unnatural or custodial death rather than close it quietly, and it defines when that duty arises. Note that the inquest is procedural, so even if the inquest is flawed or absent, Thai courts have held the prosecutor may still have power to prosecute the underlying crime. If a relative died unexpectedly or in custody, understanding the inquest process early helps you protect the family's position before any court inquiry.
Supreme Court decisions interpreting this section
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Supreme Court Judgment No. 21697/2556 (2013)
A death in military custody still falls under section 148 paragraph one, and the court of the locality where the corpse is located has authority to inquire and make an inquest order.
Even though the deceased was an active-duty soldier held in a military prison, section 148 paragraph one applied, and the inquiry and order followed the Criminal Procedure Code, applicable by analogy under the Military Court Constitution Act because military criminal procedure had no specific inquest rules; the court where the corpse was located had authority.
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Supreme Court Judgment No. 2410/2530 (1987)
The inquest under section 148 is part of the inquiry official's evidence-gathering, so even without an inquest the prosecutor may still have power to prosecute where the investigation was otherwise lawful.
Answering the defence that the prosecutor lacked power to prosecute because no inquest was held, the court held the inquest is part of the investigative evidence-gathering under section 148, so where the investigation was otherwise lawful, the absence of an inquest did not deprive the prosecutor of power to prosecute.
Curated decisions with case numbers verified against the Supreme Court database. English renderings are the firm's editorial translation for study.
Frequently asked questions
When is an inquest required in Thailand?
Under section 148, an inquest is required whenever it clearly appears or is reasonably suspected that a person died unnaturally, or died while in official custody, except for a lawful execution.
What counts as an unnatural death?
Section 148 lists five categories: suicide, being killed by another person, being killed by an animal, death by accident, and death by a cause not yet ascertained.
Is a prosecution void if no inquest was held?
Not necessarily. Thai courts have treated the inquest as part of the investigation, so a lawful investigation may still support the prosecutor's power to prosecute even where an inquest was not held.