As a one-time student of constitutional law, I remember all too
well the shocking hypothetical scenarios lecturers loved to
propose. For example, what if Parliament passed a law requiring all
blue-eyed babies to be killed at birth? It is absurd, horrifying,
and – crucially – impossible in practice. This one stuck with me,
thanks to my lecturer, the inimitable Jeff Murray, who used it to
illustrate just how extreme parliamentary sovereignty can be. As AV
Dicey once observed, legislators “must go mad before they could
pass such a law, and subjects be idiotic before they could submit
to it.”
The so-called “blue-eyed baby statute” isn’t just a grim thought
experiment. It exposes a core principle of UK constitutional law:
Parliament is legally sovereign. No court can strike down a primary
Act, and the monarch’s role in granting Royal Assent is purely
ceremonial.
King Charles III, no matter how outraged, could only watch,
quill trembling over vellum, as a law he despised became binding.
Royal Assent exists not to give the sovereign discretion, but to
preserve the monarchy by ensuring the Crown obeys Parliament, even
when conscience recoils.
Contrast that with Monaco, where the sovereign still wields real
legislative power. Earlier this month, Prince Albert II refused to
sign a bill legalising abortion, halting legislation despite
overwhelming parliamentary support. Monaco’s constitution
explicitly grants the Prince the right to withhold ‘promulgation’ –
a rare but entirely legal exercise of conscience. Across Europe,
very few monarchs retain similar influence. Belgium’s King Baudouin
refused to sign an abortion law in 1990, Luxembourg amended its
constitution after Grand Duke Henri blocked a euthanasia bill in
2008, and Liechtenstein’s Prince Hans-Adam II has publicly said he
would veto any abortion reforms. Monaco is a modern exception,
where a single individual can still reshape the law.
The blue-eyed baby thought experiment shows the limits of power
in practice. While Parliament in the UK is legally supreme, its
authority is constrained by ethics and public opinion. Legislators
may theoretically be able to pass extreme laws, but doing so would
be self destruction. Dicey’s scenario highlights the tension
between law and morality.
These examples reveal how differently constitutional systems
handle power. In the UK, parliamentary sovereignty is absolute on
paper, but tempered by elections and public accountability. In
Monaco, the Prince is constitutionally empowered to intervene,
embedding his own idea of conscience directly into law-making. Both
systems rely on checks beyond the law itself: public opinion,
ethical norms, and the opinions of those in power.
Ultimately, the blue-eyed baby statute is more than a classroom
exercise. It reminds us that laws may be technically absolute, but
morality, conscience, and institutional safeguards define the
boundaries of legitimate authority. In the UK, the monarch obeys to
preserve the institution; in Monaco, the sovereign may act to
‘protect’ it – yet in both cases, it is the balance between law and
ethics that really matters.
