There are a number of reasons why selectors in charge of deciding cabinet composition should value public opinion on individual ministers. Public evaluations of ministers may act as a non-electoral instrument of ministerial accountability, by offering the selectorate additional information to identify underperformers, dishonest or simply unsympathetic cabinet members who could harm government and selectorate’s electoral chances and (eventually) policy goals. Also, this argument could be extended to the case of ministers who contribute positively contribute to those goals. Related to this, information from public evaluations may also help individual members of the selectorate to recognize political competitors – in case cabinet members may compete with them to occupy a position within the selectorate.

However, despite those reasons, there is no systematic empirical evidence showing that, in fact, selectors (do or do not) value and use public opinion as a key element to manage cabinet composition and dynamics. This paper aims to be a first contribution to fill that gap, using quarterly data from public opinion surveys measuring the level of knowledge and public evaluation of individual cabinet members of the Spanish governments since 1994. It tests the hypothesis of the significant impact of the level of knowledge and public evaluations on the duration and careers of Spanish ministers between 1994 and 2010. This is done against other types of contextual and individual information the selectors – in this case, the Spanish PM – may use to manage cabinet composition and its dynamics. In case the main hypothesis is confirmed, the sign of the coefficients of relevant independent variables will also shed light on the way public opinion is interpreted by the selectors.