Criminal defamation in Thailand continues to be a subject of significant legal debate, often involving politicians, journalists, activists, and private individuals. The legal framework is articulated in the Penal Code and further supplemented by procedural regulations under the Criminal Procedure Code. Judicial authorities, particularly the Supreme Court, have issued pivotal rulings that elucidate evidentiary burdens and permissible defenses (see https://fosrlaw.com/2023/criminal-defamation-litigation-in-thailand/).
This article examines the evidentiary standards applicable to criminal defamation, including the function of the preliminary hearing, the admissibility of electronic evidence, and pertinent case law.
Legal Basis: Penal Code Sections 326–328
Section 326: Imputing a fact to another in a manner likely to damage their reputation constitutes defamation, punishable by up to one year in prison or a fine of up to 20,000 baht.
Section 327: Extends liability to defaming the deceased if it harms the family’s reputation.
Section 328: Covers defamation by publication or broadcast (including social media), with increased penalties of up to two years’ imprisonment and/or a fine of up to 200,000 baht.
Defamation is a compoundable offense, meaning prosecution requires the injured party’s complaint, filed within three months of discovering the offense.
The Computer Crimes Act and Online Defamation
The Computer Crimes Act (CCA) traditionally expanded defamation prosecutions because Section 14(1) criminalized posting false data online. However, the 2017 amendment removed Penal Code defamation from Section 14(1), limiting its scope to false data that endangers public or national security. Regular online defamation now falls under Penal Code Sections 326–328. Still, Section 16 of the CCA criminalizes uploading images that cause defamation, with penalties of up to three years in prison and fines up to 200,000 baht.
Preliminary Hearing: Prima Facie Evidence Requirement
Because criminal defamation is usually initiated by a private complaint, Thai procedure requires a preliminary hearing (CPC Section 165). This hearing serves as an initial trial to determine if the complainant’s case has enough merit to proceed.
– Standard of proof: The complainant must present prima facie evidence for each element of the offense, credible enough to justify moving forward to trial. This threshold is higher than a simple accusation but lower than proof beyond a reasonable doubt.
– Judicial function: The judge determines whether the complaint is frivolous or vexatious. If so, the case is dismissed.
– Defendant’s rights: Since the 2019 amendment, CPC Section 165/2 allows defendants to submit evidence at this stage — documents, witnesses, or legal arguments — to show that the case has no merit.
Case example: In Supreme Court Decision 3050/2544, the Court dismissed a defamation case at the preliminary stage because the complainant failed to specify the exact defamatory statements. Without clear prima facie evidence of harmful statements, the case could not proceed. Therefore, the preliminary hearing serves as a safeguard, filtering out weak or politically motivated complaints before a full trial.
Consequences for the Accuser When a Case is Dismissed
If a criminal defamation complaint is dismissed at the preliminary hearing stage for lack of prima facie evidence, Thai law outlines potential consequences for the complainant:
1. Immediate Dismissal with Prejudice: According to Section 161/1 of the Criminal Procedure Code, if the judge finds that the complaint was filed in bad faith, involved distorted facts, or was intended to harass, the case will be dismissed with prejudice and cannot be refiled.
2. Malicious Prosecution Liability: A dismissal under Section 161/1 CPC may allow the accused to pursue a claim for malicious prosecution, including a civil damages suit for harm caused by the unfounded complaint.
3. Judicial Finding of Abuse of Process: A formal declaration that the complaint was frivolous or malicious could damage the credibility of the complainant in future legal cases and may serve as evidence in related litigation.
4. Costs and Reputational Impact: The complainant might be ordered to pay court fees and expenses. Also, a dismissal due to lack of merit, especially in high-profile cases, may harm the complainant’s reputation.
Burden of Proof at Trial
If the case moves beyond the preliminary hearing, the complainant or prosecution must prove guilt beyond a reasonable doubt. At trial:
- The prosecution must demonstrate that the accused made or published the defamatory statement to a third party.
- If the defendant claims truth (Penal Code Section 330), the burden shifts to the defendant to prove that the statements are true. However, truth is not a defense if the statement pertains solely to private matters without public benefit.
- Exceptions under Section 329 (fair comment, official duty, public criticism, court reporting) remain available defenses.
Evidence Rules in Practice
Electronic Evidence:
- The Electronic Transactions Act (Section 11) states that data messages, including emails, social media posts, and digital files, cannot be excluded solely because of their electronic form.
- The Criminal Code Act (Section 25) confirms that government authorities can lawfully obtain computer data and present it as evidence under the Criminal Procedure Code.
- Judicial authorities need proper authentication, which may involve linking a Facebook post to the defendant through metadata, witness testimony, or Internet Service Provider (ISP) records.
Testimonial Evidence:
- Witnesses, including the complainant, are required to testify in court; hearsay evidence is generally considered inadmissible.
- The defense has the right to call witnesses to support claims based on truth, public interest, or good faith.
- Judges can question witnesses but usually do not introduce new evidence themselves.
Supreme Court Rulings and High-Profile Cases
- Supreme Court Decision 626/2563 (2020): Ruled that defamatory Facebook posts count as “publication” under Section 328. Multiple posts are considered a single offense and are punished under the harsher provision.
- Supreme Court Decision 3050/2544 (2001): Dismissed a case because the complaint lacked specific defamatory allegations at the preliminary stage.
High-profile examples reported by Thai and international media include:
- Phuketwan case (2015): Journalists Alan Morison and Chutima Sidasathian were cleared of criminal defamation and CCA charges after republishing a Reuters report. The court determined the report was truthful and in the public interest.
- Andy Hall cases (2014–2016): A human rights researcher faced multiple criminal defamation lawsuits. Several were dismissed due to procedural problems, and he was ultimately acquitted, illustrating the safeguards at the initial stage.
- Senator v. Rangsiman Rome (2024): A 100-million-baht defamation lawsuit was filed against a Member of Parliament, with the Criminal Court holding a preliminary hearing, as reported in the Bangkok Post. The case highlights the importance of the initial hearing stage. Even in cases involving public figures and large damage claims, the complainant must still present prima facie evidence before the case can move to trial. This demonstrates the key safeguard discussed earlier: without credible initial evidence, even high-profile or politically sensitive complaints may not advance.
Conclusion
Proving criminal defamation in Thailand requires strict evidentiary and procedural standards. The preliminary hearing acts as a key safeguard, demanding prima facie evidence before the case can proceed. Once accepted, the burden of proof shifts to demonstrating guilt beyond a reasonable doubt. Thai law also recognizes electronic evidence as admissible if it is authenticated. Court rulings from the Supreme Court (see: https://fosrlaw.com/2025/supreme-court-cases-acceptance/) emphasize the importance of defamation charges and highlight protections for defendants, mainly through defenses like truth, fair comment, and the filtering role of the preliminary hearing.
About the Authors
M.L. Numlapyos Sritawat is a founding partner of Formichella & Sritawat and leads the firm’s Litigation and Dispute Resolution practice. With over thirty years of courtroom experience, he has appeared before nearly every level of Thailand’s judiciary, including the Supreme Court. A titled member of the Royal Institution and descendant of a prominent Thai legal family, M.L. Sritawat is well known for his assertive and innovative advocacy, as well as his ability to handle highly complex disputes across civil, commercial, bankruptcy, and criminal law. He frequently represents clients in precedent-setting cases, and his extensive knowledge of Thailand’s courts and procedural law makes him one of the country’s top litigators.
Phalavat Kosalanon is an associate at Formichella & Sritawat and a key member of the firm’s Litigation Department. He specializes in pre-litigation strategy, dispute resolution, and trial preparation, regularly assisting with both corporate and regulatory disputes. His practice includes intellectual property litigation, cross-border defamation cases, and complex commercial conflicts. Known for his methodical preparation and litigation tactics, Phalavat supports the firm’s senior partners in managing document-heavy trials and developing innovative strategies to tackle new issues before Thai courts.
The comments herein are for discussion and information purposes only and are not guaranteed to be up to date. Nothing herein should be or can be relied on as legal advice.
For any questions, you may contact Formichella & Sritawat at [email protected]
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