Facts
On 12 July 1985, the Federal Tribunal rendered a judgment in which it recognized the right of certain affected owners (the expropriated parties) to receive compensation for the formal expropriation of their neighborhood rights due to the noise pollution caused by the operation of Geneva Airport. The Federal Tribunal then had to resolve several fundamental questions regarding the calculation of this compensation, in particular the date to be taken into account for the assessment of the market value of the expropriated property ("dies aestimandi"), the starting date for the payment of interest on the compensation, as well as the modalities of compensation in the form of in-kind benefits (soundproofing measures).Considerations
The Federal Tribunal first recalled its previous case law prior to the adoption of Art. 19bis of the Federal Expropriation Act (ComPurA), according to which the decisive date for the calculation of the market value of the expropriated right was the date of the decision of the assessment commission. However, given the particularities of the procedure in these cases, the Tribunal considered it necessary to adopt special solutions.
Thus, the Tribunal set the "dies aestimandi" in the autumn of 1985, i.e. before the various conciliation hearings that were held successively between 1987 and 1993. This single date for all cases makes it possible to take into account the significant variations in land prices and construction costs that occurred during this period.…