Sustainable Tourism Law

318 SUSTAINABLE TOURISM LAW 20/2013 regarding authorizations, seeing as in addition to subjugating them to the principle of proportionality, it limits the justifying reasons and requires that the principles of necessity and proportionality be proven to be sufficiently in line with this law. So, to sum up, two aspects of the law ensuring market unity deserve to be mentioned: first (art. 5), the subjugation of government regulations that restrict open access to and the practice of economic activities to greater requirements, i.e., the aforementioned overriding reasons of public interest that can justify such restrictions (principle of necessity) and the subjugation of the restrictions to the principle of proportionality, and secondly (art. 17), the subjugation of the restrictive regulations, when they entail administrative intervention mechanisms, to differing levels of requirements, i.e., for authorizations, with even more demanding constitutional stipulations and a greater restriction on applicable overriding reasons of public interest; for sworn statements, requirements for justifying the overriding reason of public interest and that the requirements be proportional; and for communications, it must be pertinent to better understand the number of economic agents, installations and physical infrastructures that exist in the market. B.II. The application of the principles of necessity and proportionality in the touristic commercialization of residences When considering the aspects that have been discussed above in terms of their application to tourism, and specifically the touristic commercialization of residences, the principles of necessity and proportionality, and their application, must be duly considered by autonomous community-level legislators when regulating this economic activity. And they should be based on the fact that accommodation activities taking place under the banner of touristic commercialization specifically occur in installations or physical infrastructures (dwellings) for which the eventual requirement of an authorization to allow access to this economic activity is subject to an important condition, namely that the activity is susceptible to damage the natural and urban environments, public health and safety, and historical and artistic heritage (section 1.b, art. 17, Law 20/2013). Were this not the case, access to this activity would be subject to a less restrictive mechanism, such as a sworn statement or a communication, in line with the requirements established in sections 2 and 3, respectively, of the previously cited article.