In a commentary, SMU Associate Professor of Law Eugene Tan opined that cross-border cooperation must go beyond diplomacy and declarations to clear the air. He argued that the ASEAN’s agreements and plans to tackle transboundary haze have done little to bring the perpetrators to justice. Assoc Prof Tan highlighted that the Singapore’s Transboundary Haze Pollution Act (THPA), enacted in 2014, has resulted in no prosecution after more than a decade, as successful prosecution requires strong cooperation from foreign authorities, particularly Indonesia, to obtain evidence. He said that full and effective implementation of ambitious regional commitments on transboundary pollution remains ASEAN’s Achilles heel. Assoc Prof Tan stated that the haze is as much an environmental issue as a political one, reflecting domestic governance and the lack of rule of law in polluting states. He called for ASEAN to ensure member states robustly implement and enforce their treaty obligations, establish mandatory cross-border evidence sharing and demonstrate a genuine willingness to prosecute offenders.