The denunciation of the "political scandals" and the stigmatization of the "corruption" became during the last fifteen years a major dimension of what we usually call a "crisis of democracy" or a "crisis of political representation". The surveys administered in France during the past 25 years showed that people evaluate their "political leaders as being rather corrupted". In 1977 this opinion was shared only by 38% of the respondents, but it grew to 55% in 1990 and reached 64% in 2000. In the survey conducted in February 2006 the result was 62% This paradoxical situation is also related to the decrease in political confidence and the crisis of political representation. The integrity crises seem to be a major component of the "loss of confidence" in public institutions. The severity of judgements as regards the corrupted political personnel does not automatically imply a form of denunciation. The central hypothesis is that the attitudes and capacity to react to the political corruption is connected with two dimensions: the interest related to politics (degree and form of participation) and the confidence in public institutions. In this respect, the practice of denunciation is a part of policy competence, more than a moral attitude.