Governing Alternative Marine-Fuel Releases Under International Maritime and Environmental Law

The decarbonisation of shipping is accelerating the uptake of alternative marine fuels, but the legal architecture governing ship-source incidents re- mains largely calibrated to oil. This article argues that the resulting mis- match is not merely technical: it exposes a structural deficit in accountability for non-oil bunker releases. Examining the IMO liability, compensation, preparedness and pollution-prevention regimes alongside UNCLOS Part XII, the article shows why current instruments fail to provide a predictable and technology-neutral pathway for liability and redress. It then develops precau- tion and the polluter-pays principle as interpretive benchmarks for fuel- specific due diligence and cost allocation pending reform. On that basis, it advances two targeted IMO responses: effects-based definitional drafting with a residual compensation mechanism, and calibrated modernisation of limitation rules for high-risk alternative-fuel incidents.