Who Gives Evidence to Parliamentary Committees? A Comparative Investigation of Parliamentary Committees and their Constituencies

This article focuses on the interaction between parliamentary committees and external . How is the interaction organised, and how does it influence which interests are ? The authors show that institutional variation in procedures for calling witnesses variation in committee agendas influence both the composition of actors and the concentration evidence. By composition of actors, they refer to the set of different actor involved. By evidence concentration, they refer to the extent to which evidence is by a relatively small share of active actors. The study is based on a new data of all contacts between parliamentary committees and external actors in one year three countries: the United Kingdom, Denmark and the Netherlands. Interestingly, findings show that procedures of invitation rather than open calls increase the diversity actor composition and decrease the concentration of actor evidence. This, however, at a cost, since the overall volume of contacts is reduced.