When administrative authorities are deciding in the administrative procedure on the first as well as on the second instance, they are often facing the question of which adequate substantial provision to apply. Bounded to the principle of legality, the administrative authorities have to use the provisions in force when deciding on the rights, obligations and legal interests of the parties; according to the interpretation of Article 6(1) of the Slovenian Administrative Procedure Act, set by the administrative theory and practice, this means that the authorities must use the provisions which are in force when a first-instance decision is issued. However, it still remains disputed whether the administrative authorities are also bounded to the principle of legality when reconsidering the same matter in cases where the first-instance decision had been annulled in the appeal proceedings due to the substantial or procedural violations, while the substantial provision applied when accepting the first-instance decision has changed in the meantime. This does not raise an issue when it is already clarified within the new provisions. Nevertheless, since the legislator does often not resolve this question when adopting new substantial provisions, the administrative authorities usually face a big problem when reconsidering the remitted decision; due to the non-uniform administrative and judicial case-law, it is not clear to them, which provision to apply.
The present master thesis will analyse how the changed of substantial provisions affect the decision-making in the administrative procedure. The author will introduce arguments, which speak in favour of the view that a new provision has to be used when reconsidering the decision, and also the arguments which speak against this point of view. Some other questions, which are raised in the administrative practice with regard to the provision alternation, will also be presented. At the end, the author will adopt her own position and present a regulation de lege ferenda regarding the application of the substantial law from the temporal view.