A New Silenus Box: The French Manual on the Law of Military Operations


| Jun 21, 2023

French manual

French armed forces have participated in more than a hundred military operations since 1995. Enhanced operational activity notwithstanding, France strives to consistently keep its military operations in line with international law. The new French Manual on the Law of Military Operations contains a lot of essential information toward that end. Although austere in appearance, it conceals many pearls of wisdom and basic rules of behavior. As such, it looks like the Silenus Box to which Alcibiades compared Socrates: ugly and hollow on the outside, the statue of Silenus contained tiny golden statues of the gods. In a similar manner, the new French manual should be a trustworthy guide as well as a source of inspiration for all French legal advisers and, more generally, for all French militaries wherever they are serving.

The Need for a New Manual

More than a statement of intent, respect for international law is a binding as well as a guiding principle for France, which is one of the founding members of the United Nations and one of the five permanent members of the United Nations Security Council. It is noteworthy that this principle appears many times in the French legal system. First and foremost, it was enshrined in the preamble to France’s Constitution of 27 October 1946 (para. 14), which is still an integral part of the current French Constitution. Moreover, it is embodied in a number of international legal instruments to which France is a State party, starting with the Charter of the United Nations and the four Geneva Conventions. The importance of international law is also evident in the French criminal code and the French defense code, which establish an exemption from criminal liability for any French soldier who uses force or direct coercion measures provided this is necessary for the accomplishment of the mission and in compliance with international law.

However, in debates regarding French military operations, legal issues usually remain in the background. Instead, discussions generally focus on how military operations can be funded and once completed, whether funds have been used effectively or efficiently to achieve the desired end state. It is therefore not surprising that, unlike some other permanent members of the UN Security Council such as the United States and the United Kingdom, or some other member States of the European Union, France did not feel the need to have a genuine manual on the law of military operations. Consequently, for many years, what was known as the French manual of the law of armed conflict was primarily a lexicon. As no document brought together France’s interpretation of the international law applicable to military operations, French legal experts and other interested people used to refer to incomplete and scattered documents.

Over the years, the demand for a reference handbook has grown steadily within the French Ministry for the Armed Forces. Factors such as the very wide range of contemporary military operations, the increasingly high expectations of the public, the media and members of parliament for greater transparency and accountability concerning military action, and the growing role of national and European courts in the interpretation and application of international humanitarian law (IHL) and international human rights law (IHRL) have highlighted the importance of a clear and suitable legal framework with relevant rules of engagement and appropriate and well-trained staff, including legal advisers. In light of this, the Legal Affairs Directorate and the joint military staff of the French Ministry for the Armed Forces decided in 2019 to write a compendium on the way in which international law is interpreted and applied by the French armed forces in the conduct of military operations.

At the end of a four-year writing process, which included consultations with inter-ministerial partners such as the French Ministry for Europe and Foreign Affairs, the French Ministry for the Armed Forces presented its Manual on the Law of Military Operations in February 2023. In a single volume of 375 pages, this document presents the main rules governing the use of force when the French armed forces operate abroad in situations of armed conflict or on domestic territory in peacetime, while emphasizing current legal as well as operational issues. It also devotes an important place to the rules governing land, sea, air, cyber, and outer space military operations and to compliance mechanisms.

The Manual’s Objectives

The Manual’s objectives are three-fold. The first of these is political. After unveiling in 2019 both a declaration on the application of international law in cyberspace and a space defense strategy, France is now going a step further with its Manual on the Law of Military Operations.

As a follow up to these two previous statements, this manual is another way for France to highlight its determination to respect international law in the conduct of its operations and more broadly to act upon its commitments under IHRL, especially those arising under the European Convention on Human Rights. This manual is also a way for France to reaffirm that IHL remains a relevant framework for the conduct of hostilities and the protection of civilian populations, in whichever domain they take place (air, land, sea, outer space or cyberspace). Moreover, the manual is further evidence of France’s desire to make its interpretation of international law, which may not always match that of its partners, more readable and transparent. Basically, the accessibility of the manual is likely to facilitate cooperation and reduce the risks of misunderstanding and uncontrolled escalation.

The second objective is operational as the manual is designed help the military command carry out its mission. Under the French defense code, French soldiers must obey the lawful commands of superiors and they are responsible for carrying out the missions entrusted to them. On the one hand, this means that in performing their duties, members of the French armed forces shall comply with the law. In addition, they shall refuse to carry out an order to perform a clearly wrongful act or an act that constitutes a breach of international law as it applies in armed conflict. On the other hand, it means they cannot be ordered, and they cannot perform acts, which are contrary to the laws and customs of war and international treaties.

Therefore, the new French manual is intended to help French military legal advisers and the entire chain of command fulfil their mission. Under Article 82 of the first Additional Protocol to the Geneva Conventions, in each theater of operations, operational legal advisers must be appointed to assist the chain of command, to participate in the operational planning process, and to ensure continuous compliance with IHL. As such, they are responsible for ensuring that all airmen, sailors, and soldiers understand the rules of engagement and, where necessary, for providing them with useful information or training. In this regard, the manual will constitute an essential educational tool for the French armed forces. It will also be of great assistance when French service personnel train State partners or non-State armed groups to respect IHL. From this perspective, it will complement the tools already in use within the French armed forces. For instance, during their current intervention in the Sahel region, French soldiers have provided armed groups with a combatant’s booklet translated into eight local languages of the region. This booklet includes illustrations and basic reminders with a view to promoting respect for IHL.

The third objective is legal. The manual on the law of military operations will allow France to better advocate for its operational practice and its interpretation of the rules of law applicable to military operations. In that respect, the manual should be very useful if France or its representatives are brought before national, European, or international courts in relation to its military operations. Because the absence of such a manual has been regarded as a factor of fragility within the French armed forces, drawing up a compendium that reflects and supports the French military’s established practices became a priority.

The Manual’s Structure

Unlike other States’ manuals, which primarily follow a thematic format, the French manual on the law of military operations draws a distinction between armed forces’ interventions either within or outside French national territory. The manual presents the principles governing the use of force for each of these situations.

The manual details, firstly, the legal framework that governs the use of force on national territory in the event of exceptional circumstances, such as a state of war, siege or other public emergency, or in support of civil action for defense or security purposes. As a result, the manual is not only about IHL. That is one factor that differentiates the manual from those of other States.

The manual then addresses the rules applicable to the use of force in situations of international and non-international armed conflict. It sets out the specific obligations that apply to the armed forces regarding the protection of civilians and civilian property, the choice of means and methods of warfare, and the targeting process. It further examines how people can be deprived of their liberty in situations of armed conflict, how they should be treated, what procedures should be followed, and what should happen when they are released or transferred. The manual focuses on existing (judicial and non-judicial) mechanisms to ensure respect for IHL as well as domestic mechanisms that offer legal protection for French soldiers against what would otherwise be an excessive legalization of the acts carried out in an operational context.

To fulfil its objective, the manual refers to several bodies of law, both international and domestic, including IHL, IHRL, the law of the sea, space law, and criminal law. It is based on an analysis of reference sources and studies as well as on related internal documents and materials of the French armed forces. Military legal experts contributed their expertise to each topic, with a subsequent review by the operational law division of the joint military staff and the office of international and operational law of the Legal Affairs Directorate of the French Ministry for the Armed Forces. All processes were conducted in close cooperation with the French Ministry for Europe and Foreign Affairs to ensure that the manual also complies with official French positions.

Lastly, to be as accessible and convenient as possible for military end users as well as the general public, the manual includes many concrete examples and focus points. Its rationale is indeed to be practical and operational.

The Manual’s Stance on the Application of IHRL to Armed Conflict

The manual aims to address the main issues the French armed forces may face during the planning and the execution of operations. One such issue relates to the different bodies of law applicable in times of armed conflict. This is one of the most sensitive and complex questions to deal with. The manual therefore examines situations where various branches of law need to be reconciled and then identifies the rules to be applied in these situations.

It is well known that IHL and IHRL are two distinct but complementary bodies of law. They are both concerned with the protection of life, health, and human dignity. While IHL only applies in armed conflict, the manual recognizes that IHRL always applies, in peacetime and in wartime. As a result, the protection regimes of IHL and IHRL partially overlap. Over the years, with the increasing complexity of contemporary forms of conflict and the continuous debate on the lex specialis principle, the interplay between these two bodies of law has become a particularly critical issue for many armed forces. As a result, in many practical situations, both the conduct-of-hostilities and the law-enforcement paradigms can be used. But applying one instead of the other, or both at the same time, can provide radically different results and create issues for the operating forces as well as for the protection of the people concerned.

Given the significant activity of the French armed forces over the past thirty years, the manual had to provide answers to these thorny questions, in particular those situations not yet addressed by case law. The manual therefore states France’s domestic position that IHL is regarded as the lex specialis that applies to situations of armed conflict, at least regarding the conduct of hostilities. Accordingly, provided that force is used in accordance with the fundamental principles of IHL, violence to the life and person of combatants, as well as civilians taking a direct part in hostilities, is lawful. Similarly, there is no requirement to investigate any death or damage resulting from the conduct of hostilities unless it appears that IHL violations have been committed.

However, the manual is not only IHL-centric. It takes into account the case law of the European Court of Human Rights on how to balance IHL and IHRL. Considering human rights in situations of armed conflict leads the French armed forces to adjust their operational practices every time they exercise control over territory or over any individual, even outside French territory. Consequently, in situations where individuals disappear or are found injured or dead while under the control of the French armed forces, the manual provides for the measures to be taken to ensure that the resulting investigations are effective and independent. Likewise, in non-international armed conflict, persons deprived of their liberty in the custody of French armed forces now benefit from material and procedural guarantees inspired by those applicable in international armed conflict or resulting from IHRL.

The Manual’s Stance on Other Issues

Another issue that highlights the application of IHL alongside other bodies of international law is environmental protection. As the lex specialis during armed conflicts, IHL grants general protection to the environment against the effects of hostilities, as it does for any other civilian object. It also offers special protection to the natural environment against widespread, long-lasting, and severe damage. In addition to IHL obligations, some rules of international environmental law may continue to apply in the context of armed conflicts. Consequently, the French manual sets out the regime pertaining to environmental protection in armed conflict, the principles for the assessment of incidental damage to environment that may result from the conduct of military operations, and prohibited methods of warfare. It echoes the French viewpoint that international environmental treaties apply in situations of armed conflict only if these instruments were negotiated with this in mind or include specific provisions concerning the conduct of military operations.

The French manual also deals with other contemporary military issues, such as the new challenges posed by cyber and space operations.

Concerning cyber warfare, the manual firstly describes the nature of that domain and the French cyber chain of command. Then, it describes how international law applies to cyberspace, both in peacetime and conflict situations. As such, the manual includes the positions detailed in France’s 2019 major statement on international law and cyber operations. Unsurprisingly, it reaffirms the application of the principle of sovereignty to cyberspace and therefore that the most serious violations of sovereignty, especially those that infringe France’s territorial integrity or political independence, may violate the prohibition on the threat or use of force, which applies to any use of force, regardless of the weapons employed. It subsequently details the responses authorized under international law in reaction to a cyber operation constituting an internationally wrongful act. The manual indicates that a cyberattack that causes damage of a significant scale or severity may constitute an armed attack, leading to a right to respond in self-defense. The manual further examines how IHL applies to cyber operations carried out in, and in connection with, an armed conflict. In that respect, it focuses on how the French armed forces must implement the fundamental principles of IHL when they operate in cyberspace.

Concerning the space domain, after recalling that the principle of the peaceful use of outer space is compatible with some military space operations, the manual follows the way paved by the French space defense strategy in 2019. The manual discusses peacetime military space operations as well as military space operations conducted in armed conflict. It details the types of military operations that may be carried out in outer space as well as the possible responses that may be taken in the event of an unfriendly act, an internationally wrongful act, or a prohibited use of force perpetrated in or from outer space. In this regard, the manual clearly articulates that a hostile act directed against a space system in outer space may constitute a use of force or even an armed attack if its scale and effects are significant. Among the space matters covered, the manual examines and details the conditions under which IHL applies to military space operations in the event of armed conflict. Thus, it addresses the factors that make the space domain so unique and the respect for IHL principles so difficult. These include the duality of space objects, the risk of causing incidental harm to civilian objects or populations in outer space or on the earth, as well as the neutrality of non-belligerent states.

Another contemporary military issue the manual considers is the protection of cultural property. In many recent armed conflicts, the damage caused to cultural heritage is not only collateral but also caused deliberately. Therefore, the manual details the duties and obligations of French soldiers in this regard. The manual recalls that cultural property enjoys general protection, which makes any use of it for military purposes and any attack conditional on the existence of imperative military necessity. This can only be invoked if and for as long as there is no feasible alternative available to obtain a similar military advantage. The manual also specifies that cultural property may benefit from a higher degree of protection if it is registered for either special protection or enhanced protection. The higher the degree of protection, the greater the constraints concerning a potential withdrawal of immunity of the property concerned.

Concluding Thoughts

It is not possible in this short post to summarize the entire manual the French Ministry for the Armed Forces published at the start of this year. Instead, I hope that it will encourage people to read the manual, to write about it, and discuss its content.

Law, whether international or domestic, plays a key role in all the operational activities of the French armed forces, regardless of where they take place. However, there is widespread misunderstanding of the law’s role. One of the purposes of this manual is therefore to highlight how the law affects the planning and execution of French military operations. Another purpose is to emphasize how the law protects and enables the French armed forces to accomplish their mission. Respect for the law and for human dignity is inseparable from operational success, because it is one of the key conditions for military forces to be reliable and legitimate in the eyes of civilian populations. With this manual, such respect should remain the benchmark for the French armed forces’ actions.


LTC Mickael Dupenloup is a legal adviser within the French armed forces.


Photo credit: Guillaume Cabre, French Army