By Assoc Prof Dr Shahrul Mizan Ismail
The duty to prevent dangerous pollution does not begin when a neighbouring government sends a letter.
Malaysia should be prepared to pursue an international claim over transboundary haze if credible evidence establishes that Indonesia failed to meet applicable international obligations.
Concern should be translated into a legal assessment of whether any breach can be established, supported by defensible evidence and realistic remedies.
The ASEAN Specialised Meteorological Centre activated its highest regional haze alert on 26 August 2026. Its monitoring has also recorded smoke drifting from Kalimantan towards Sarawak.
That supports investigation. It does not, by itself, establish Indonesia’s legal responsibility for every Malaysian loss.
From haze alert to legal responsibility
The legal foundation already exists. Malaysia and Indonesia are parties to the ASEAN Agreement on Transboundary Haze Pollution. Its provisions address monitoring, prevention, preparedness and emergency response.
Article 4(2) requires prompt responses to requests for relevant information or consultations where transboundary haze originates within a party’s territory. Article 12(4) requires a prompt decision and notification on an offer of assistance.
The Agreement also contains broader preventive and monitoring obligations that do not depend on a formal diplomatic protest. The specific duties concerning information, consultations and assistance arise in the circumstances prescribed by the Agreement. But neither does the treaty make Indonesia automatically liable whenever smoke crosses a border.
The central question is whether Indonesian authorities exercised the diligence required by international law.
In Pulp Mills, the International Court of Justice (ICJ) explained that due diligence involves appropriate regulation, vigilant enforcement and administrative supervision of public and private operators.
Malaysia should therefore investigate whether there were specific regulatory or enforcement failures. Were known fire risks addressed before the dry season? Were recurring violations investigated? Were enforcement orders implemented? Were warnings followed by reasonable preventive measures?
Indonesia must have an opportunity to supply evidence of its response. Extreme weather and difficult terrain matter to the assessment. So would evidence showing whether reasonable precautions were available and, if so, whether they were taken.
Private plantation fires need not be treated as government acts. A state may nevertheless incur responsibility for a failure to discharge its own regulatory duties, where such a failure is established.
The ICJ’s 2025 climate advisory opinion reinforces that distinction, although it does not decide this haze dispute.
Building the evidence for a claim
Malaysia should take four practical steps.
First, Wisma Putra and the Attorney General’s Chambers should consider issuing a formal notice seeking information and consultations, while reserving Malaysia’s legal rights should the evidence ultimately support a claim. Emergency cooperation should continue.
Second, independent experts should connect fires, pollutant transport and Malaysian exposure. Satellite observations must be tested against ground measurements and atmospheric modelling.
Domestic pollution sources and scientific uncertainty must be included. A hotspot is an investigative lead, not proof of who started a fire.
Third, quantify losses caused by the alleged breach. Additional treatment, monitoring and emergency expenditure should be supported by records.
The ICJ’s 2018 Costa Rica-Nicaragua compensation judgment recognised environmental damage as compensable, while requiring a sufficiently direct and certain causal connection.
Malaysia must explain what injury adequate diligence would have prevented or reduced.
Fourth, secure a lawful route to a binding decision. The haze treaty provides consultation or negotiation, not compulsory adjudication.
An ICJ case requires a valid basis of jurisdiction. Malaysia should propose a special agreement, arbitration or a bilateral claims commission with independent experts and binding awards.
UNCLOS deserves separate examination if evidence establishes relevant marine pollution. Smoke passing above the sea is insufficient.
Jurisdiction, procedural requirements and exceptions must be addressed before litigation is threatened.
From evidence to enforcement
An initial 90-day programme should produce an evidence dossier, a provisional loss account and a reasoned proposal for settlement or adjudication. These are proposed administrative targets, not treaty deadlines.
Any implicated Malaysian companies should face the same scrutiny. Nationality cannot become an excuse for selective accountability.
Malaysia already has legal tools. It needs the discipline to use them. The absence of a protest cannot erase an existing duty; the absence of a serious legal strategy would be harder to explain.
-- BERNAMA
Dr Shahrul Mizan Ismail is an Assoc Prof at the Faculty of Law, Universiti Kebangsaan Malaysia.