When it comes to the police, we think first and foremost of "institution", namely a body organized into specific units or services, bringing together a certain number of members. Most of the time, they wear a uniform so that they can be identified and their rights and duties are governed by law, clarified by a more or less extensive regulatory framework. The bodies thus exercise determined functions in a specific territory..
The institutional approach is essential for the police historian. It is even a prerequisite for any research mobilizing or carrying the police object. It is indeed necessary to understand the "rules of the game": it comes down to knowing the face theoretical fonts at any given time, to then understand the real practices – and the inevitable adaptations that result. In this context, there are many points of attention: they touch the organization, to structures, the staffing and regulatory missions of police units. They also affect the hierarchical control of these. Finally, attention is focused on the articulation between the different police forces active in a territory, to see how each other's skills and missions are complementary or competing. This amounts to questioning the notion of a police system, defined as the assembly of different active policies at a given time in a territory. To finish, the researcher will be interested in the causes explaining the face of the police at a given time. This is a reflection of society, and in particular of his fears in the face of "risks" or "insecurity" factors. In this way, it is an analytical grid resulting in particular from police sociology that must be applied both to each police institution, but also to the systems where they evolve, to characterize them in terms of local or national presence; of civil or military identity; general or specialized missions.
This sole process of knowing the "face" and "cadre" of the police is largely insufficient.. On the one hand, the researcher must be aware that the institutional approach only offers a partial and limited vision of the complexity of the police thing. It does not provide an in-depth understanding of the realities of police practices and the human aspect that underlies them.. Police practices are certainly framed by structures and rules, but they also depend on a multitude of complementary factors, including the demands of the populations or the priorities/possibilities of the police. Above all, the only institutional vision erases the historicity of the police. In particular, it suggests the police as something that evolves only by the rules, while the reality is much more nuanced. For various reasons, the rule may not or no longer be applied. On the contrary, it can reflect the acceptance of a practice or an organizational logic already at work. Finally, the rule can also be abused either for ease, or for political reasons (wars, political transitions, economic crises, etc.)