Landmark decisions ([0], [1]) set precedent. The conseil constitutionnel has ruled that its precedent is binding [2]. In fact the majority of current constitutionnal law in France was willed into "constitutionnal" status by a landmark decision of the conseil [3]. I mean precdent can move _laws_ to the _constitution_ (see [4]). That seems pretty binding and persuasive.

[0] https://fr.wikipedia.org/wiki/Grands_arr%C3%AAts_en_droit_ad...

[1] https://fr.wikipedia.org/wiki/Grands_arr%C3%AAts_de_la_Cour_...

[2] https://www.conseil-constitutionnel.fr/decision/1962/6218L.h...

[3] https://fr.wikipedia.org/wiki/D%C3%A9cision_Libert%C3%A9_d%2...: essentially, the council ruled that the preamble of the constitution also had constitutional value (which was not the case previously and still is not for laws) - since it also mentions other texts (the preamble of the 1046 Constitution, the 1789 Bill of rights, etc. those texts also have the same legal power as the constitution.

[4] https://en.wikipedia.org/wiki/Fundamental_principles_recogni...

That's how it works in Germany, and in principle our systems are similar enough.

In Denmark, another civil law system the highest court can give judgement in cases of principal character that should be followed in the future.