Often bills cannot be dealt with conclusively during committee discussions even if the preparatory work by the parliamentary groups has been very detailed. If the subject matter of the bill is very complex, and the bill concerns a politically controversial piece of legislation, then a public hearing of experts and representatives of interest groups is held (see p. 31f). This is now almost always the case when a major bill is introduced, as it was for our example. One of the reasons for holding a hearing is to obtain additional specialist information and advice about particular problems relating to the bill in order to assist the progress of deliberations. Another purpose of the public hearing is to attract media interest in the bill, make the significance of the issues involved clear and encourage political debate. The parliamentary groups therefore regularly endeavour to choose experts whose assessment of the difficulties, risks or chances of success of the bill either backs up their own political views or is likely to undermine the arguments of opposing parliamentary groups. The same also goes for representatives of powerful organisations such as employers’ federations, trade unions or environmental organisations. The views such groups express publicly on a particular bill have a potential influence on the committee’s views. Thus, amendments to bills are sometimes the result of a public hearing in the committee. In the past, bills have even been withdrawn because the majority or all of the experts invited to a hearing considered the proposed legislation either inappropriate or harmful. Holding a hearing therefore serves to widen participation in the discussion of important laws and ensure that the involvement of interest groups is more effective and, in particular, more public. It is no coincidence, therefore, that there has been a steady increase in the number of hearings held during electoral terms. Indeed, the fact that the U.S. Congress holds several different hearings every day on every conceivable subject is an illustration of this tendency.