The aim of this paper is to study the relationship between the party organisation and the use of different digital tools. We will analyse the parties which are represented in the Catalan parliament: CiU, ERC, PSC, PP, ICV, C’s, CUP. Our guiding hypotheses are two: 1.- Parties with a high decision-making centralization degree offer on their webpages fewer interaction online tools in comparison to the less centralised ones; 2.- But, online interaction on the party social networks, such as Facebook and Twitter, does not relate with the parties’ decision- making centralisation degree. The reason why is that participation in parties’ Facebook pages and Twitter depends much more on the issues arising in the political context and the party’s appropriation of these issues. Meanwhile the online channels for interaction offered by the parties via their webpages are fully designed by the parties, the social networks functionalities are predetermined and its use depends much more on the issues at stake and the corresponding party’s position. We will measure the level of party centralisation following the codification scheme of Janda (1980) and the party site’s online interactive channels taking into account the measurements carried out by Gibson (2013), Cardenal (2013), Gibson et al (2012), Wall and Suddulich (2010) and Padró-Solanet and Cardenal (2008). Regarding the data on parties’ Facebook pages and their Twitter accounts, we will analyse their basic elements and the type of interaction. With regard to Facebook, we will study the number of the parties’ posts together with their links, videos, photos as well as the total number of likes, shares and comments derived from these posts. In the case of Twitter we will analyze the number of followers and the average of people following party user per day, the party user’s tweets, the number of hashtags raised by the party user and the number of tweets following a party hashtag.
