Introduction

Interdicting drug smugglers is a well-recognised head of coastal state jurisdiction over vessels within national waters. It may be impractical, however, to wait for traffickers to enter territorial or contiguous waters before taking action. Drug-running ‘mother ships’ may sit in international waters, distributing their cargo to faster, smaller boats to convey ashore at night. Major treaties creating high-seas boarding rights to address this problem are the 1988 UN Narcotics Convention, a 1990 Spanish–Italian treaty, the 1995 Council of Europe Agreement, and numerous US bilateral agreements with neighbouring states. Most create procedures allowing one party to request permission to board another's flag vessel, without imposing any obligation to permit arrests or seizure. It is convenient to begin with the historic bilateral practice between the United States and the United Kingdom, culminating in the 1981 US–UK Exchange of Notes, which may have influenced later developments.

US–UK bilateral practice on smuggling

Modern treaty law on smuggling interdiction has its origin in the 1924 Liquor Treaty between the United States and the United Kingdom, which aimed at combating rum-running during Prohibition. The United States had, in the years preceding the treaty, taken to arresting vessels ‘hovering’ in international waters if by means of their small boats (or boats coming out from shore) they had participated in running liquor ashore. At the time, the United Kingdom vigorously opposed such action as incompatible with international law and in order to avoid what it saw as an attempt to extend the effective breadth of the territorial sea.