Despite its fashionableness, the law relating to the protection of the marine environment is an extremely important subject. Unfortunately, the quality of much that has been written on the subject is not commensurate with its importance; in particular, the legal technique deployed is frequently somewhat loose.

This book is a happy exception. What the author does is carefully to analyse the general international law rules relating to jurisdiction, state responsibility and the law of the sea, before applying them to the specific topic of the marine environment. The approach is therefore traditionally analytical and positivist, which is a welcome change from the school of thought which believes that, if we pretend for long enough that the Emperor has a splendid suit of new clothes, they will suddenly materialize. Dr Smith’s exposition of the traditional areas of the law is admirable. Though economical and lucid, his exposition also manages to raise most of the difficult problems in these branches of the law. So good are these accounts that they could be read with great profit by students of general international law with no interest in the environment. But the real pay-off comes, of course, when he actually applies these doctrines to his specific area of study, and his careful analysis yields some very useful conclusions.

That is not to say that I had no reservations. In the first place, though his method is in general very good, the author sometimes tends to be satisfied with relatively little evidence in support of the existence of a rule when this satisfies his thesis (see, e.g., pp. 42, 90 in fine and 114). He also tends in places to display what I consider to be too great a readiness to infer rules of customary international law from multilateral treaties, and he needs to make it clearer how in his view decisions of international organizations or conferences can be sources or evidence of customary international law.

Turning to the substance, I did regard as rather questionable Dr Smith’s view (pp. 157ff.) that merchant ships exercise an element of the authority of their flag state, so as to engage its responsibility. Just because the flag state has a claim in respect of interference with freedom of navigation, etc., it does not follow that the merchant ship is acting as an agent or instrumentality of that state. His second reason—that the degree of state subsidy etc. of merchant fleets means that they are not so “private” as might appear—has rather more substance, but is certainly not universally true and seems insufficient to carry the argument.

Dr Smith believes that a state which has jurisdiction over a vessel, either because it is the flag state or is the state of nationality of the owners, has an obligation to exercise due diligence with regard to those states whose environment might be harmed by the vessel’s activities. In the case of ultra-hazardous activities, or possibly those where the potential damage is very great indeed, he would impose strict liability. Where the ship is directly under a state’s control, such as a warship, these propositions and the application he makes of them in specific instances would not appear to be particularly exceptionable. However, in the case of merchant ships it sometimes leads to some rather questionable conclusions. For example, at