The classical legal tradition offers a rich, nuanced understanding of governance, particularly in its treatment of the separation of powers, which modern legal thought tends to oversimplify. While liberal constitutionalism insists that the rule of law demands strict separation between those who make, enforce, and adjudicate the law, the classical approach reveals a more flexible, historically grounded view of legality. It contends that the fusion of powers does not necessarily result in arbitrary governance, nor does it violate the rule of law. Rather, the combination of roles within a single office can promote a more effective and just application of the law.
The classical view, as seen in the legal systems of ancient Rome and medieval Europe, often placed lawmaking and adjudication in the same hands. This was not seen as a departure from the rule of law, but rather as a way to ensure that laws were enforced effectively and that justice was served. Emperors, kings, and other rulers, while wielding substantial authority, were often bound by legal norms that emphasized their duty to administer justice impartially. This tradition, exemplified by figures like Emperor Hadrian, who famously reversed his course to hear a commoner’s petition, shows that even centralized power could operate within a framework of legality.
Liberal theorists argue that without the separation of powers, law becomes a mere tool for tyranny. But this view ignores the deep, historical cultures of legality that existed long before modern constitutionalism. In the Roman and medieval worlds, law was not simply imposed from above; it was a living system of norms shaped by jurists, scholars, and courts. Even though the powers of lawmaking and adjudication were often fused, the rule of law persisted through a shared commitment to justice.
Indeed, modern liberalism’s fixation on separating powers obscures the fact that the rule of law requires more than just institutional arrangements. The classical legal tradition emphasized that justice and legality arise from the responsible use of power, not its mere division. Frederick II’s Liber Augustalis, for instance, proclaimed that justice and enforcement must be united to ensure the proper application of the law. Combining powers was seen as a way to make governance more effective and grounded in the realities of law enforcement and adjudication.
The classical tradition also teaches that the combination of powers can foster a deeper integration of law and justice. In modern administrative states, such as the United States, the combination of rulemaking, enforcement, and adjudication within agencies is not a violation of the rule of law, but a practical response to the complexity of governance. Agencies must adapt laws to the intricate realities of the cases before them. Judicial review, while important, cannot replace the nuanced understanding that comes from exercising multiple powers within a single body.
The obsession with separating powers also risks diminishing the role of internal norms. In systems where powers are combined, the officials involved often switch roles, moving from lawmaking to adjudication. These shifts, governed by a commitment to the proper administration of justice, do not inherently lead to bias. Indeed, the classical tradition understood that those holding power could act impartially even when performing different functions. Modern courts, such as the U.S. Supreme Court, have similarly upheld the legitimacy of combined powers, recognizing that the mere combination of functions does not necessarily result in unfairness or partiality.
The classical approach to the rule of law reflects a broader conception of constitutional governance, one that seeks not only to protect individual rights but also to promote the common good. This view, articulated by scholars like Adrian Vermeule, recognizes that the rule of law is not simply about limiting state power but about ensuring that law serves the general welfare. The separation of powers, while useful in certain contexts, is not an end in itself. The ultimate goal of any constitutional system is to secure justice and peace for the polity, a goal that may sometimes require a combination of powers.
The classical legal tradition provides a valuable counterpoint to the modern liberal emphasis on the separation of powers. It reminds us that the rule of law is not a one-size-fits-all concept but a flexible, historically contingent ideal that can take different forms depending on the needs and circumstances of the polity. By focusing too narrowly on institutional design, modern legal theory risks losing sight of the deeper purposes of law: the promotion of justice, the protection of rights, and the advancement of the common good. The classical tradition offers a richer, more adaptable understanding of how law can achieve these ends, even when the powers of governance are not strictly separated.