Fundamentals

Guarantist Constitutionalism: Rights, Guarantees, and Limits on Power

By Daniel Sardá · Published on August 31, 2026

9 min read1,851 words

Guarantist constitutionalism subjects legislation to constitutional limits of both form and substance. A guide to its concepts, scope, and tensions.

Guarantist constitutionalism is a theoretical model associated with the Italian jurist Luigi Ferrajoli. Its starting point is straightforward: a rigid constitution does more than establish who may make laws and through which procedures. It also imposes limits and obligations on what those laws may provide.

The consequence is significant. A law may have been enacted by the competent body in accordance with every prescribed step and still be invalid if it violates a constitutional right. Political authority is therefore bound not only by procedural rules but also by higher norms governing the substance of its decisions.

This approach should not be confused with a generic defense of rights or with the claim that judges must resolve every constitutional conflict. It is a specific theory about the structure of the legal order, the guarantees that make rights operative, and the limits the constitution places on every public authority.

Key idea: In the guarantist model, the constitution is not a declaration of aspirations standing outside the law. It is positive law that conditions the validity of lower-level norms.

What Makes This Constitutionalism “Guarantist”

Ferrajoli presents guarantist constitutionalism as a form of reinforced legal positivism. This may sound paradoxical. Positivism is often identified with obedience to any law in force, but that is not the claim here. A rigid constitution is itself part of positive law, and it subjects legislation to higher conditions.

Rigidity means that the constitution cannot be amended in the same way as an ordinary statute. Its provisions also bind the legislature: some govern the lawmaking process, while others prohibit infringements of rights or require their protection. Constitutional substance thus serves as a standard of validity.

This account extends across the constitutional order a logic already present in penal guarantism. The latter focuses on limiting punitive power through rules such as legality, the presumption of innocence, and due process. Constitutional guarantism applies the logic of limits and binding obligations to public powers as a whole and to all constitutionally protected rights. The two concepts are therefore related but not interchangeable.

Nor is it synonymous with liberal constitutionalism. Both are concerned with limiting power and protecting individual spheres, but they emerge from different theoretical traditions. In addition to liberties, Ferrajoli’s guarantism encompasses social rights and positive obligations whose fulfillment may require legislation, institutions, and public resources.

A Law Can Be in Force Without Being Valid

Understanding the model requires separating three questions that everyday language often blends together:

• Existence or being in force: Was the norm produced by the competent authority through the established procedure?
• Validity: Are its form and substance compatible with the higher norms that govern its production?
• Effectiveness: Is the norm observed and applied in practice?

In Ferrajoli’s vocabulary, these properties do not necessarily coincide. Imagine a statute enacted by parliament, promulgated, and applied by the administration. The norm exists and may be effective. Yet if it establishes discrimination prohibited by the constitution, it is substantively invalid within the model.

The reverse is also possible: a constitutionally valid norm may have little effectiveness because authorities fail to comply with it or lack the institutional capacity to implement it. Legal validity alone does not ensure that reality conforms to the law.

This distinction makes it possible to criticize a legal order from within. One need not first appeal to a morality outside the law to argue that a lower-level statute contradicts the constitution: the higher positive norm provides the standard. Terminology varies among schools of legal thought, but the distinction between existence, validity, and effectiveness is central to the guarantist architecture set out by Ferrajoli.

Having a Right Does Not Mean Having All Its Guarantees

The second crucial element is the distinction between rights and guarantees. For Ferrajoli, a right expresses a normative expectation: that someone provide something or refrain from interference. Guarantees are the duties, prohibitions, and institutional mechanisms that correspond to that expectation.

In his study of the constitutional guarantees of fundamental rights, Ferrajoli distinguishes between two levels:

• Primary guarantees are the duties and prohibitions corresponding to the right. If freedom of expression exists, for example, public authorities have a duty not to censor speech except in circumstances constitutionally permitted.
• Secondary guarantees come into play when a primary guarantee is violated. They include mechanisms for determining that a violation occurred and, depending on the case, annulling the act, imposing a sanction, or providing redress.

A court that invalidates a prohibition incompatible with a constitutional liberty operates at the second level. But it would be a mistake to reduce all guarantees to judicial remedies. Many depend on legislative rules, administrative procedures, oversight bodies, or institutions capable of delivering a service.

Consider a social right recognized by the constitution when no institution exists to provide it, no procedure is available for claiming it, or no responsibilities have been assigned. The right does not disappear because these elements are missing. On this account, the legal order has a guarantee shortfall that it must correct. Proclamation and effective protection are distinct matters, as the discussion of constitutional guarantees explains in greater detail.

Useful distinction: A right and its guarantees are not the same thing. Recognizing the former does not automatically create every means needed to protect or fulfill it.

Antinomies and Gaps: Two Different Defects

The preceding distinction reveals two kinds of legal defect. An antinomy arises when a lower-level norm contradicts a higher limit. A statute authorizing state conduct that the constitution forbids is a typical example.

A gap, by contrast, arises when a norm or institution required to satisfy a higher obligation is missing. If the constitution recognizes a right that requires implementing legislation and the legislature fails to create the necessary duties or procedures, the problem is not a contradictory rule but an absent guarantee.

The distinction also allocates institutional responsibilities. Faced with an antinomy, a reviewing body may set aside the invalid norm within the powers assigned to it by the relevant legal system. Addressing a gap generally requires the legislature or another competent authority to enact the missing rules. Courts may identify the omission or activate available remedies, but that does not give them unlimited authority to design public policy.

Ferrajoli assigns legal scholarship both a critical and a constructive dimension: it should identify contradictions between normative levels and show which guarantees are missing. Identifying a defect, however, does not remedy it. When fulfilling a right requires scarce resources, coordination, or technical decisions, the legal diagnosis leaves questions of priority and institutional design unresolved.

Democracy Has Both a Formal and a Substantive Dimension

Guarantist constitutionalism does not dispense with elections, representation, or majority rule. Instead, it distinguishes between two dimensions of democracy, an account Ferrajoli also develops in his 2006 study. The formal dimension answers who decides and through which procedures. The substantive dimension determines what no majority may decide and what constituted authorities must secure by virtue of constitutional rights.

A parliamentary majority may enact a law in full compliance with procedural rules and still cross a substantive limit. If it could vote to abolish a minority’s political freedom, democratic rules would become available to destroy the conditions of democracy itself.

From a classical liberal perspective, subjecting majorities to higher norms has a clear affinity with constitutional government: electoral legitimacy does not make power unlimited. The law protects spheres that ordinary political decision-making should not invade.

The overlap is not complete. The scope of positive obligations, the constitutionalization of social rights, and the latitude granted to reviewing institutions generate disagreements both within and beyond liberalism. Nor does “substantive democracy” mean that any decision considered just is therefore constitutional. Within this theory, the term denotes the limits and binding obligations established by higher positive norms.

Key idea: Voting determines who governs, but a rigid constitution also determines which powers the winner receives and which rights remain beyond the winner’s reach.

Guarantism and Principialism Are Not the Same Approach

Ferrajoli contrasts his model with principialist constitutionalism. In his account, guarantism seeks to preserve the conceptual separation between law and morality and to defend the binding force of positive constitutional norms. His criticism targets the general treatment of rights as moral principles subject to balancing, since this could weaken their obligatory character and expand interpretive discretion.

This distinction must be drawn carefully. Principialism is not simply judicial arbitrariness, nor is the interpretation of constitutional rules mechanical. Legal texts use open-ended concepts, rights may come into tension, and concrete cases require reasoned argument. The disagreement concerns how these norms should be understood and how their application should be disciplined—not a simplistic choice between judges who obey and judges who invent.

What the Model Contributes—and What It Leaves Unresolved

The model’s most visible contribution is that it takes constitutional supremacy seriously. If rights are binding norms, they provide standards for challenging exercises of power even when ordinary procedures have been followed. The distinction between rights and guarantees also prevents a solemn proclamation from being mistaken for real protection. And the categories of antinomy and gap show that law can fail through both what it commands and what it omits.

That same design raises important objections:

• Democratic deficit and paternalism. Placing certain matters beyond majority control protects rights, but it also removes decisions from ordinary politics. Julián Gaviria has argued that this architecture can weaken elements of popular sovereignty and place too much trust in unelected institutions (2019).
• Judicial discretion. Judicial review can curb legislative abuses, but review without clear standards and powers can disrupt the separation of powers. The guarantist response is to bind judges to positive law as well; the practical difficulty of interpreting open-ended provisions remains.
• Rights without the capacity for fulfillment. Treating the absence of guarantees as a gap preserves the right’s normative force, but it does not create resources, capacity, or agreement on priorities. The theory identifies an outstanding obligation; institutions must determine how to fulfill it.
• The distribution of power. Neither absolute trust in majorities nor absolute trust in courts fits comfortably within a system of limited powers. The design of review, accountability, and the remedies available in each legal order all matter.

Warning: Constitutional review can limit the legislature, but it does not make the judiciary an unlimited power or replace the responsibility to create missing guarantees.

An Architecture for Evaluating Power

Above all, guarantist constitutionalism offers a vocabulary for examining the distance between a constitution and the operation of the legal order. It asks whether laws respect higher conditions, whether each right has adequate corresponding duties and remedies, and whether contradictions or omissions prevent those rights from becoming effective.

Its promise is to subject all power—including majority power—to legally binding rights. Its enduring tension lies in doing so without diluting democratic deliberation, overburdening judges, or turning constitutional aspirations into promises without instruments. Understanding this tension is more useful than calling every system that lists rights “guarantist”: the distinctive feature lies in the concrete network of limits, obligations, and institutions intended to give those rights practical force.