Malaysia is being urged to prepare an international legal claim against Indonesia over transboundary haze pollution, following the activation of the highest regional haze alert by the ASEAN Specialised Meteorological Centre on August 26. The agency recorded smoke drifting from Kalimantan in Indonesia towards Sarawak, prompting calls for investigation into Indonesia’s compliance with its obligations under the ASEAN Agreement on Transboundary Haze Pollution.

Both Malaysia and Indonesia are signatories to this regional treaty, which outlines responsibilities related to monitoring, prevention, preparedness, and emergency response to transboundary haze. Article 4(2) of the agreement mandates prompt responses to requests for information or consultations when haze originates from within a party’s territory. However, treaty provisions do not automatically assign liability to Indonesia whenever smoke crosses the border. Instead, the central issue is whether Indonesian authorities have exercised the due diligence expected under international law to regulate and control activities that cause haze.

Legal experts cite precedents such as the International Court of Justice’s (ICJ) 2010 Pulp Mills case, which emphasized the necessity for states to enact appropriate regulations, enforce rules vigilantly, and supervise public and private actors effectively to fulfill their environmental obligations. Malaysia is advised to investigate whether Indonesian authorities acted adequately in addressing known fire risks before the dry season, investigating repeated violations, enforcing orders, and implementing preventive measures. It is further stressed that Indonesia should be given the opportunity to present evidence regarding its response efforts, taking into account factors such as extreme weather conditions and challenging terrain.

The distinction between state responsibility for direct government acts and for failures to regulate private entities also features prominently in the discourse. Fires occurring on private plantations may not constitute acts of the Indonesian government, but state liability may arise from inadequate regulatory oversight. This position aligns with the ICJ’s 2025 advisory opinion affirming states’ binding legal duties under international law to protect the climate system and prevent environmental harm.

To address the issue, a four-step approach has been proposed for Malaysia. First, its Ministry of Foreign Affairs (Wisma Putra) and Attorney General’s Chambers should issue a substantiated notice of claim. This would outline the obligations allegedly breached, request relevant records and consultations, and reserve Malaysia’s right to seek compensation. Second, independent experts should analyze the connections between identified fires, pollutant transport, and haze exposure in Malaysia by integrating satellite data, ground measurements, and atmospheric modeling, while also accounting for domestic pollution and scientific uncertainties.

Third, Malaysia is encouraged to quantify the losses attributable to the alleged breach, including expenses related to medical treatment, environmental monitoring, and emergency response, supported by thorough documentation. The ICJ’s 2018 judgment in a different environmental case recognized that environmental damage can justify compensation when a sufficiently direct causal link is established. Fourth, efforts should be made to secure a lawful mechanism for binding dispute resolution. As the haze treaty offers consultation and negotiation but not compulsory adjudication, Malaysia may explore options such as a special agreement, arbitration, or a bilateral claims commission employing independent experts with authority to issue binding decisions.

Additionally, if marine pollution is implicated, examination under the United Nations Convention on the Law of the Sea (UNCLOS) may be warranted, although airborne haze over maritime areas alone may not suffice to trigger jurisdiction. Procedural and jurisdictional prerequisites must be navigated carefully prior to any litigation.

An initial 90-day investigative program has been suggested to compile an evidence dossier, provisional loss assessments, and proposals for settlement or adjudication. This timeline is intended as an administrative target rather than a treaty-imposed deadline. The call extends to Malaysian companies potentially implicated in contributing to the haze, emphasizing that nationality should not shield entities from accountability.

Observers note that Malaysia already possesses the necessary legal frameworks to address the issue but must demonstrate the resolve and discipline to utilize them effectively. The absence of formal protest letters from the Malaysian government does not negate its responsibility to act, and failure to develop a comprehensive legal strategy to address transboundary haze may be difficult to justify.