The Doctrine of Continuous Chase: An Advanced Legal Analysis of the Right of Hot Pursuit

The Right of Hot Pursuit is one of the most remarkable exceptions to the principle of “Flag State Sovereignty” on the high seas. While the high seas are traditionally an area of total freedom, the 1982 United Nations Convention on the Law of the Sea (UNCLOS), under Article 111, provides coastal states with the authority to “reach out” into international waters to prevent criminals from escaping justice. However, due to its potential to cause international friction, this right is governed by rigid procedural requirements.

1. The Jurisdictional Trigger and Spatial Limits

The legal validity of a pursuit hinges entirely on its point of origin. The Right of Hot Pursuit cannot be initiated on the high seas; it must be a domestic reaction to a violation within sovereign waters.

• Internal and Archipelagic Waters: Full jurisdiction; pursuit can begin for any violation of domestic law.
• Territorial Sea: Pursuit may begin for any breach of the coastal state’s laws, provided the passage of the foreign vessel is no longer “innocent.”
• The Contiguous Zone Exception: Crucially, if the pursuit begins in the Contiguous Zone (up to 24 nautical miles), it is limited by the “Four Interests” rule. Pursuit is only legal if the vessel has violated customs, fiscal, immigration, or sanitary regulations.
• EEZ and Continental Shelf: Hot pursuit is also applicable to violations concerning sovereign rights over natural resources or the safety of artificial installations (such as oil rigs), applying the same rules of continuity mutatis mutandis.

2. Constructive Presence: The “Mother Ship” Scenario

A vital detail in your notes is the mention of “boats or other craft working as a team.” This refers to the legal doctrine of Constructive Presence.

• If a “mother ship” remains on the high seas but uses its smaller tenders or boats to commit an offense within the territorial sea, the coastal state may initiate the Right of Hot Pursuit against the mother ship itself. The legal “presence” of the small boats is attributed to the larger vessel, justifying its arrest in international waters.

3. The Ritual of the “Stop Signal”

Maritime law requires a formal invitation to obey before force or pursuit can be utilized.

• The Visual/Auditory Requirement: The signal must be given such that it is reasonably expected to be seen or heard by the foreign vessel.
• Modern Interpretation: While UNCLOS refers to “visual or auditory” signals (flashing lights, flags, or sirens), modern practice sometimes debates the use of radio or satellite communication. However, to remain strictly within the letter of the law, traditional signals are still considered the safest legal ground for an arrest.

4. The Complexity of Aerial Pursuit

The role of aircraft adds a layer of complexity to the Right of Hot Pursuit. As you noted, an aircraft cannot simply “spot” a vessel and leave.

• The Relay Requirement: If a military aircraft initiates the pursuit by giving the stop signal, it must maintain a physical or sensory link with the vessel.
• The Chain of Continuity: The pursuit is only valid if the aircraft stays on site until a coastal state ship or another aircraft arrives to “hand over” the chase. If the aircraft returns to base before the next unit arrives, the “continuity” is broken, and a subsequent arrest on the high seas becomes an illegal act of aggression.

5. Termination: The “Sanctuary” of Foreign Waters

The Right of Hot Pursuit ends the moment the pursued vessel enters the territorial sea of its own country or a third state.

• The Rationale: Entering another state’s territorial sea brings the vessel under a new sovereign’s protection. To continue the chase would violate the territorial integrity of that third state.
• The “Escort” Exception: If the arrest was made legally on the high seas, and during the return to the coastal state’s port, the convoy must pass through the EEZ or high seas for navigational safety, the shipowner cannot claim “illegal transit.” The arrest’s legality is fixed at the moment of capture.

6. Legal Consequences of Unjustified Pursuit

International law is unforgiving regarding the abuse of this right.

• If a ship is stopped or arrested outside the territorial sea in circumstances which do not justify the exercise of the Right of Hot Pursuit, it shall be compensated for any loss or damage that may have been thereby sustained. This makes the Right of Hot Pursuit a “high-stakes” operation for Coast Guards and Navies worldwide.