Research · Institutions ·
Who guards the constitution?
Two models of judicial review, and what the choice between them says about a political system.
Abstract
Constitutional democracies must decide which body has the final word on whether a law is constitutional. This note compares the two dominant answers — review by ordinary courts, associated with the United States, and review by a specialised constitutional court, associated with Hans Kelsen and Austria — and sets out the trade-offs each involves.
Key findings
- 01Decentralised review spreads constitutional questions across the whole judiciary; centralised review concentrates them in one specialised body.
- 02The centralised model was designed partly to keep constitutional judgment out of the hands of ordinary judges, reflecting a distrust of the judiciary as much as a trust in constitutions.
- 03In both models, the method of appointing judges matters more for independence than the model itself.
The question
Every written constitution claims to be higher law. That claim is only meaningful through judicial reviewJudicial reviewThe power of a court to examine whether a law or official act is compatible with the constitution or a higher rule.↗: some institution can declare an ordinary law invalid for conflicting with it. The question this note asks is simple: which institution, and why?
Method
This is a comparative, doctrinal note. It draws on the founding texts and landmark decisions of the two models and does not attempt a quantitative comparison of outcomes.
The decentralised model
In Marbury v. Madison (1803), the United States Supreme Court held that it was "emphatically the province and duty of the judicial department to say what the law is", including when a statute conflicts with the Constitution.1 The power that followed belongs, in principle, to every court: any judge hearing a case may decline to apply an unconstitutional law, subject to appeal.
The centralised model
The Austrian Constitution of 1920, shaped by the legal theorist Hans Kelsen, took a different path. It created a single Constitutional CourtConstitutional courtA specialised court with exclusive power to review whether laws comply with the constitution.↗ with the exclusive power to annul laws.2 Ordinary judges could not set aside legislation themselves. The model spread widely after the Second World War: Germany's Federal Constitutional Court began work in 1951, and Turkey's Constitutional Court was established under the 1961 Constitution.
A short timeline
- 1803Marbury v. MadisonThe US Supreme Court asserts the power of ordinary courts to set aside unconstitutional laws.
- 1920Austrian Federal ConstitutionKelsen's design gives a specialised constitutional court the exclusive power to annul laws.
- 1951German Federal Constitutional CourtBegins work under the 1949 Basic Law and becomes the centralised model's most influential example.
- 1961Turkish Constitutional CourtEstablished by the 1961 Constitution; it began hearing cases in 1962.
Trade-offs
Concentration brings consistency and expertise; it also makes a single body an attractive target for political capture. Dispersal makes capture harder but can produce slow, uneven answers. Neither model settles the deeper question of independence, which depends on appointments, tenure and the willingness of other institutions to comply.
Limits
This note describes ideal types. Most real systems mix features of both, and practice often diverges from design.
Sources & notes
Cite this piece
The Editors, 'Who guards the constitution?' (Eunomia, 14 September 2026) <https://eunomia-henna.vercel.app/research/who-guards-the-constitution>
Continue reading
- 01What a parliament is forPassing laws is only one of a legislature's jobs, and not always the most important one.↗↗
- 02Why EunomiaAn old word for good order, and why a new publication about public life should begin with it.↗↗
- 03The quiet power of procedureWe argue about outcomes. The rules that decide how outcomes are reached deserve at least as much attention.↗↗