LEGAL FOUNDATION
What Legal Framework Will Govern Permanent Human Settlements on the Moon or Mars?
LEGAL INTELLIGENCE BRIEFING SERIES
Document Type: Legal Intelligence Brief / Advisory Memorandum
Topic Area: International Space Law
EXECUTIVE SUMMARY
The legal framework governing permanent human settlements on the Moon and Mars already exists—but only in part. International space law establishes the foundational principles governing human activities beyond Earth, yet those principles were developed during an era when space exploration consisted primarily of short-duration governmental missions rather than permanent civilian settlements. As a result, today’s legal architecture provides a constitutional framework for space activities without fully addressing the realities of long-term habitation, commercial development, municipal governance, or extraterrestrial economies.
The cornerstone of modern space law is the 1967 Outer Space Treaty, which prohibits national sovereignty over celestial bodies while preserving state responsibility for national activities conducted in outer space.¹ Additional United Nations treaties governing astronaut rescue, liability, spacecraft registration, and activities on the Moon further define the legal obligations of participating states.² Together, these treaties establish the basic legal order governing exploration but leave substantial questions concerning permanent settlements unresolved.
National legislation increasingly supplements these treaties. Countries such as the United States, Luxembourg, Japan, and the United Arab Emirates have enacted domestic laws regulating commercial space activities, licensing private operators, and recognizing rights associated with the recovery of extraterrestrial resources.³ Although these laws cannot create sovereignty beyond Earth, they significantly influence commercial behavior and provide regulatory certainty for companies operating under their jurisdiction.
The legal foundation of future settlements will therefore consist of multiple overlapping sources of authority rather than a single governing code. International treaties establish broad legal principles, national governments regulate their citizens and licensed operators, commercial agreements govern operational relationships, and customary international law will gradually emerge through repeated state practice. This layered legal framework is likely to evolve incrementally as permanent settlements transition from theoretical concepts to operational communities.
INTRODUCTION
Every legal system begins by identifying the source of legal authority. Before questions concerning criminal jurisdiction, property rights, constitutional protections, corporate governance, or commercial regulation can be addressed, it must first be determined what law currently governs activities beyond Earth.
Unlike every nation on Earth, neither the Moon nor Mars possesses a sovereign government, legislature, judiciary, or constitution. Instead, human activity in outer space is governed through a combination of international treaty law, customary international law, domestic legislation, bilateral agreements, administrative regulations, and private contractual arrangements.⁴
This layered legal architecture has developed over more than six decades and remains remarkably successful in regulating exploration. Whether it can successfully regulate permanent human civilization beyond Earth remains an open question.
- INTERNATIONAL TREATY LAW
International treaty law forms the foundation of all modern space law.
Five United Nations treaties negotiated between 1967 and 1979 collectively establish the legal principles governing activities in outer space.⁵
The most important is the Outer Space Treaty, often described as the constitutional charter of international space law.
The Treaty establishes several fundamental principles:
- Outer space shall be free for exploration and use by all nations.
- No nation may claim sovereignty over the Moon, Mars, or any other celestial body.
- States remain internationally responsible for governmental and non-governmental activities conducted in space.
- States retain jurisdiction over registered spacecraft and personnel.
- Activities shall be conducted for peaceful purposes consistent with international law.⁶
These principles continue to govern virtually every governmental and commercial activity conducted beyond Earth.
- THE FIVE UNITED NATIONS SPACE TREATIES
The Outer Space Treaty (1967)
The Outer Space Treaty establishes the legal foundation of international space law. It prohibits territorial sovereignty while recognizing continuing jurisdiction over national space activities. It remains the single most important legal instrument governing exploration, commercial operations, and future settlement planning.⁷
The Rescue Agreement (1968)
The Rescue Agreement expands obligations concerning astronauts in distress, requiring States Parties to render assistance and return personnel and space objects whenever practicable. Although drafted for governmental missions, its principles may influence future obligations involving commercial crews and permanent settlements.⁸
The Liability Convention (1972)
The Liability Convention establishes international responsibility for damage caused by space objects. Launching states bear absolute liability for damage occurring on Earth and fault-based liability for damage occurring in outer space. As commercial activity expands, this Convention will become increasingly significant for insurers and private operators.⁹
The Registration Convention (1975)
Registration establishes legal identity for spacecraft and provides the basis for continuing jurisdiction under Article VIII of the Outer Space Treaty. Future habitats, transport vehicles, and orbital infrastructure are expected to operate within this framework.¹⁰
The Moon Agreement (1979)
The Moon Agreement attempted to establish a broader international governance regime for lunar activities, including resource management under the principle of the “common heritage of mankind.” However, because it has not been ratified by most major spacefaring nations, its practical influence remains limited.¹¹
III. CUSTOMARY INTERNATIONAL LAW
Not all international law originates through treaties.
Customary international law develops through consistent state practice accompanied by the belief that such practice is legally required (opinio juris).¹²
As governments and commercial operators establish permanent settlements, customary practices concerning habitat operations, emergency assistance, resource utilization, environmental protection, and infrastructure management may gradually mature into recognized legal norms.
Historically, maritime law evolved through this process over centuries. Space law may follow a similar trajectory.
- NATIONAL LEGISLATION
International treaties establish broad legal obligations, but domestic legislation governs the conduct of individual citizens and licensed commercial entities.
Article VI of the Outer Space Treaty requires states to authorize and continually supervise non-governmental space activities.¹³ Consequently, national governments have enacted increasingly sophisticated regulatory frameworks governing commercial launch services, satellite operations, licensing, remote sensing, and space resource utilization.
This trend is expected to accelerate as permanent settlements become operational.
- INTERNATIONAL COOPERATIVE FRAMEWORKS
Modern space governance increasingly relies upon cooperative agreements that exist outside the formal treaty system.
The most significant example is the Artemis Accords, introduced in 2020 to promote interoperability, transparency, emergency assistance, preservation of heritage sites, responsible resource utilization, and the establishment of safety zones.¹⁴
Although the Accords are political commitments rather than binding international treaties, they provide important evidence of emerging state practice and may influence the future development of customary international law.
- PRIVATE LAW
Future settlements will operate through an extensive network of private legal relationships.
Commercial contracts, employment agreements, insurance policies, licensing agreements, intellectual property rights, transportation contracts, infrastructure leases, and operational manuals will govern much of daily settlement life.
In practice, many interactions between settlers will be governed by private law rather than international treaty law.
This distinction is likely to become one of the defining characteristics of permanent extraterrestrial civilization.
VII. LIMITATIONS OF THE CURRENT LEGAL FRAMEWORK
Despite its remarkable success in governing exploration, existing space law leaves numerous questions unresolved.
Current treaties provide little guidance regarding:
- Permanent municipal governance.
- Civil property systems.
- Constitutional protections.
- Criminal procedure.
- Corporate settlements.
- Taxation.
- Labor law.
- Family law.
- Elections.
- Long-term judicial institutions.
These legal gaps do not invalidate the existing framework; rather, they illustrate the distinction between governing exploration and governing civilization.
ANALYST’S ASSESSMENT
The existing legal foundation governing outer space remains both durable and adaptable. Its greatest strength lies in establishing broad principles capable of accommodating technological innovation without constant treaty revision.
Its greatest weakness is that it was designed for exploration rather than permanent habitation.
Future settlements are therefore unlikely to abandon the current legal framework. Instead, they will build upon it through domestic legislation, commercial practice, bilateral agreements, and evolving customary international law.
The legal system governing humanity’s expansion beyond Earth is not expected to emerge through a single comprehensive treaty. It will develop incrementally, reflecting operational necessity, commercial innovation, diplomatic negotiation, and decades of practical experience.
FOOTNOTES
- Outer Space Treaty arts. I–VIII.
- Agreement on the Rescue of Astronauts, the Return of Astronauts and the Return of Objects Launched into Outer Space; Convention on International Liability for Damage Caused by Space Objects; Convention on Registration of Objects Launched into Outer Space; Agreement Governing the Activities of States on the Moon and Other Celestial Bodies.
- See, e.g., U.S. Commercial Space Launch Competitiveness Act; Luxembourg Space Resources Act; UAE Space Law.
- United Nations Office for Outer Space Affairs, United Nations Treaties and Principles on Outer Space.
- Ibid.
- Outer Space Treaty arts. I–IX.
- Ibid.
- Agreement on the Rescue of Astronauts, the Return of Astronauts and the Return of Objects Launched into Outer Space.
- Convention on International Liability for Damage Caused by Space Objects.
- Convention on Registration of Objects Launched into Outer Space.
- Agreement Governing the Activities of States on the Moon and Other Celestial Bodies art. 11.
- International Court of Justice, Statute of the International Court of Justice, art. 38(1)(b).
- Outer Space Treaty art. VI.
- Artemis Accords.
SELECTED REFERENCES
- Outer Space Treaty.
- Agreement on the Rescue of Astronauts, the Return of Astronauts and the Return of Objects Launched into Outer Space.
- Convention on International Liability for Damage Caused by Space Objects.
- Convention on Registration of Objects Launched into Outer Space.
- Agreement Governing the Activities of States on the Moon and Other Celestial Bodies.
- Artemis Accords.
- United Nations Office for Outer Space Affairs. United Nations Treaties and Principles on Outer Space.
- Space Law: A Treatise.
- The International Law of Outer Space.
- The Oxford Handbook of Space Security.
This is the version I would include in the series. It stays tightly focused on the existing legal architecture, making it the foundational reference that the subsequent papers can build upon without repeatedly explaining the underlying treaties and sources of law.