Why might a prime minister appoint an independent public inquiry after a political crisis?

From the perspective of neoinstitutionalism, a prime minister might appoint an independent public inquiry following a political crisis because it has become a standard, taken-for-granted response within the political system.1

Sociological institutionalists explain this behavior by noting that political actors often adhere to specific norms or procedures because they have become institutionalized; in this context, the inquiry is perceived as the appropriate or expected way to manage a crisis. Rather than being a purely strategic calculation, this action reflects the "taken-for-granted" nature of certain institutional practices, where actors follow established scripts because they cannot easily conceive of an alternative course of action.1

By utilizing an independent body—such as one headed by a supreme court judge—the prime minister aligns their response with established institutional expectations, thereby maintaining the legitimacy of the governance regime.1