Judges are obliged to give reasons for their decisions. A set of formal and informal norms specifies how this is to be done. These norms serve a whole array of purposes. This paper shows that one substantial effect is on decision quality. The effect can even be demonstrated on an ad hoc basis. Representation norms and the actual representation activity that is brought about by them have both a cognitive and a motivational effect. They palpably hold the judge accountable for the decision taken. And they guide him through the judgment elements inherent in his task. There is interplay between both effects when it comes to combating occasional non-normative motivation, debiasing and the choice of an appropriate decision mode. More importantly even than this short-term effect is the long-term power of representation norms. They exert this power as part and parcel of a richer institutional arrangement. That arrangement reminds the judge of the professional role he is playing, and it contributes to strengthening this attitude. And the institutional arrangement helps the judge in the process of progressive expertisation. Expertisation is no absolute protection against quality defects, but it is likely to significantly improve the quality of decisions. Suggestions for the deregulation of representation norms should pay due respect to the beneficial effect these norms have on the quality of decisions.