Professor Tan Cheng Han of the National University of Singapore's law faculty explains what this means.
Q What is sovereign immunity?
A The doctrine of sovereign immunity is a principle of international law that one state cannot be sued in the courts of another state without the consent of the first mentioned state, nor will the courts of a state seize or detain property that belongs to another state.
Q What does this mean for the Terrex Infantry Carrier Vehicles?
A As the Terrex Infantry Carrier Vehicles are clearly the property of the Singapore Government, if the doctrine of sovereign immunity is applied, the outcome in principle should be the release of the vehicles.
Q What is the process for invoking sovereign immunity?
A A claim of sovereign immunity can be invoked at any time over government property that has been seized or detained.
Q Is sovereign immunity recognised internationally? Does Hong Kong recognise sovereign immunity?
A The doctrine of sovereign immunity is recognised internationally. There are decisions of the Hong Kong courts that recognise this doctrine.
Q Are there precedent cases where sovereign immunity was applied successfully?
A One relatively recent case in Hong Kong was the 2011 decision of the Hong Kong Court of Final Appeal that recognised the Democratic Republic of the Congo was entitled to sovereign immunity.
SEE OPINION: Terrex vehicles: Ball now in HK's court