The theory of constitutional pluralism suggests that interacting legal orders that are (or claim to be) constitutional in nature need not—and should not—necessarily be regarded as being hierarchically arranged, with one ‘on top of’ the others. Rather, the relationships between the orders can be conceived of heterarchically. However, there is an assumption in much of the literature that the ‘interface norms’ that regulate the relationships within such a heterarchy are universal by nature, capable of undifferentiated application across differing constitutional orders. This thesis examines whether interface norms are in fact universal by nature, or whether they are relationship- and context-dependent, taking as its field of study three interacting legal orders—those of Ireland, the European Union, and the European Convention on Human Rights. It uses an established model of constitutional pluralism based on ‘coordinate constitutionalism’ to test the assumption of universality across three constitutional frames: the ‘vertical’ relationship between Ireland and the European orders, the ‘horizontal’ relationship between the European orders, and the ‘triangular’ panoply of state, Union and Convention. Having analysed the interface norms at work in these relationships, both in isolation and in the round, the thesis concludes that these norms are not in fact universal, and that different conceptions of constitutional pluralism need to pay much greater attention to the specific nature of any given constitutional order and its relationship with other orders in the constitutional heterarchy.

Alors que la tolérance administrative a longtemps été caractérisée par sa précarité absolue vis-à-vis de ceux qui en bénéficient, l’administration pouvant décider de revenir brutalement à une application des règles de droit, l’évolution récente du droit positif remet en cause cette conception traditionnelle. La Cour européenne des droits de l’homme juge en effet que la tolérance administrative d’une construction irrégulière sur un terrain public permet de reconnaître à son bénéficiaire un droit au respect de ses biens. Cette césure entre droit français et droit européen invite à une étude du phénomène. Elle invite d’abord à en proposer une définition. A cet égard, la tolérance administrative désigne juridiquement le fait, pour une autorité administrative, de s’abstenir volontairement et illégalement d’utiliser les moyens dont elle dispose pour sanctionner une illégalité commise par un administré. Cette définition permet de faire le départ entre la tolérance et de nombreuses notions avec lesquelles elle est parfois confondue. Elle invite ensuite à en proposer un régime juridique orienté sur la protection des bénéficiaires de tolérance. Fondé sur le nécessaire respect de la confiance légitime créée par certaines tolérances, ce régime général permettrait notamment d’empêcher que l’administration revienne brutalement sur son comportement. / For quite some time, the administrative tolerance was characterized by a precarious situation for those who beneficiate from it. The Administration could indeed abruptly decide to operate a strict return to lawfullness. Nowadays, this traditional conception is being questionned by the recent evolution of positive law. Regarding an irregular construction on public land, The European Court of Human Rights ruled in favor of the administrative tolerance's beneficiary, acknowledging his right to have his property respected. The caesura existing between French and European law is worthy of further study. First of all, rises the necessity of a definition. Thereupon, the legal notion of administrative tolerance refers to the fact, for an administrative authority, to willingly and illegaly abstain from using the means in its power to sanction the irregularity perpetrated by an administered. The notion of administrative tolerance is often mixed up with others, hence the need for a definition as a starting point. The next step would then be to suggest a legal regime, oriented towards the beneficiaries of the tolerance. Based on the idea that the legitimate trust emanating from some tolerances must be respected, such a regime would notably prevent the Administration from revising its position.

La chute du communisme en 1989 a constitué un énorme défi pour les Etats européens qui l’ont connu. Les nouvelles démocraties, confrontées à l’immense héritage du passé, ont dû faire face à la question des individus liés à ce régime, et en particulier ceux qui ont travaillé ou collaboré avec les services secrets communistes. La lustration constitue une réponse originale des Etats postcommunistes à ce phénomène. Elle est considérée comme une mesure de justice transitionnelle. La lustration est strictement encadrée par des lois. Celles-Ci mettent en place des procédures permettant de juger le comportement passé des personnes souhaitant exercer des emplois dans la fonction publique du nouvel Etat démocratique. De ce fait, ces lois mettent en place une sorte de purification de la fonction publique. Les procédures de lustration possèdent un caractère contraignant, car elles peuvent violer de nombreux droits et libertés fondamentaux des personnes qu’elles visent. D’où l’importance de l’encadrement de ce phénomène à différents niveaux: au niveau national par les cours constitutionnelles et au niveau européen par le Conseil de l’Europe et la Cour européenne des droits de l’Homme, qui a établi des standards de lustration à respecter par chaque Etat souhaitant la mettre en oeuvre. / The fall of communism in 1989 was a huge challenge for European states who experienced its effects. The new democracies had to face the immense legacy of the past, and had to find a solution on the issue of individuals related to the former regime. In particular, they had to work with those who have worked or collaborated with the communist secret services. Lustration is an original response the Post-Communist States to this phenomenon. It is considered as a measure of transitional justice. Lustration is strictly regulated by laws. They set up procedures to verify the past behavior of persons wishing to pursue employment in the public service of the new democratic State. Therefore, these laws establish a kind of purification of public administration.The lustration procedures are binding because they may violate many rights and fundamental freedoms of the individuals they are targeting. Hence, the importance of the supervision of this phenomenon at different levels: at the national level by the constitutional courts and at the European level by the Council of Europe and the European Court of Human Rights, who has established the standards of lustration to be respected by each State wishing to implement it.