In a democratic society, evaluating the design and effects of public policies fulfils different political and technical functions. First, it fosters transparency regarding political actors’ actions and their outcomes. This provides for accountability and democratic control by Parliament and citizens. Second, it enables the strengthening of the decision-making process via valuable information to enhance the effectiveness and efficiency of public policies. Therefore, when “evidence-based policies” are promoted, it is both a technical argument in favour of effectiveness and a political statement in favour of citizens’ and their representatives’ democratic control of the power. Of course, some political matters cannot solely be based on quantitative evidence or purely technical criteria. Clear limits exist, imposed by the issues’ complex nature, the availability of information and the capacity of social sciences to analyse and make reliable and unambiguous projections within the timeframes in which society requires suitable answers for the challenges it faces. And one of economists’ core tasks should indeed be to highlight those limits, so that the findings of the assessments and analyses are appropriately interpreted with the due caveats. But to acknowledge and highlight these limits (especially on the ability to assess ex ante, i.e. to foresee in real time the different outcomes that may ensue from different courses of action in the many key areas when faced with complex problems) should not check our ambition for these assessments to influence the decision-making process. While not definitive, their conclusions act as an objective reference which is relevant to achieving the intended aims of public policies.

Assimilating the long-term view that price stability requires is harder for the political power, which may have incentives to prioritise shorter-term considerations tied to the electoral cycle. The grounds for the independence of central banks are thus general interest considerations. Firstly there is the belief that such independence benefits society far more than if the powers were to be directly assumed by the political authority. And further is that fact that the legitimacy resulting from this independence is conferred by a decision of the State’s highest political institutions (parliaments). Independence must of course go hand in hand with guarantees as to the professional competency and personal integrity of the members of the independent body, especially of its 1/6  BIS central bankers' speeches  senior officers, and controls over, and accountability for, their actions. Control and accountability are also crucial to adequate institutional quality. Yet aside from independent central banks being an example of effective institutional design when it comes to incorporating long-term considerations into our democratic societies, I wish to use my address to outline three complementary matters. These are, in my view, essential to encouraging the public authorities to include these long-term considerations in economic policy decision-making, and how independent institutions such as the Banco de España can make a decisive contribution. An assessment culture to launch us forward The first of these three matters stems from the incorporation of an ongoing and thorough publicpolicy assessment culture.