Dutch politicians’ use of cost–benefit analysis

28 Dutch politicians and 10 top-level civil servants were interviewed about the way Dutch politicians use cost–benefit analysis (CBA). Various types of use were identified. Politicians use CBA: (1) When forming their opinion about the desirability of transport projects; (2) As political ammunition (opportunistic use); (3) To make themselves and their decisions look more rational (symbolic use). None of the politicians stated that they solely base their judgment on CBAs. Politicians mention seven barriers that hamper the use of CBA when forming their opinion: (1) The process of forming an opinion is trivial; (2) Politicians prefer to form their opinion based on conversations rather than on reading reports; (3) Politicians don’t trust CBA’s impartiality; (4) Politicians disagree with normative choices made in CBA. An example of such a normative choice is that CBA attaches an equally large weight to everybody’s utility changes. (5) Politicians think that CBA’s explanatory power is limited; (6) Politicians receive CBAs too late; (7) When there is plenty of money, politicians care less about a project’s social profitability. Members of Parliament identified barriers 3 and 6 as the most important barriers. They regard publishing CBAs one or two months before a debate as the most auspicious solution for rectifying these barriers. An interesting observation is that no barriers for the opportunistic and symbolic use of CBA by politicians were identified. Hence, it can be concluded that it is highly likely that when politicians receive CBAs for transport projects, they will use the CBA in an opportunistic and symbolic way, but politicians will not necessarily use CBA when forming their opinion.