Robert Alexy (born 9 September 1945 in Oldenburg, Germany) is a jurist and a legal philosopher.

[3] Since 2008 the Universities of Alicante, Buenos Aires, Tucumán, Antwerp, National University of San Marcos in Lima, Prague, Coimbra, Porto Alegre, Belo Horizonte, Chapecó, Rio de Janeiro and Bogotá awarded him the honorary doctorate degree.

In The Argument From Injustice, Alexy defends Radbruch's formula that injust or evil laws only lose their legal validity when they deliberately disavow justice and equality.

He formulated law's relationship to morality on three theses: At the heart of his theory is the claim to correctness: Law must necessarily claim to be correct, no matter how corrupt, lest it be self-contradictory and fundamentally illogical.

As law coerces behaviour and gives individuals decisive reasons for acting, the correctness it claims must also be moral.