From constitutional discretion to the positivist weight formula

A correct understanding of balancing discretion shows how proportionality works as an internal limit of discretion and how suitability, necessity and proportionality in the narrow sense constrain the choices to be made by a legislative normative authority. On the other hand, an accurate contraposition between the laws of balancing (the content of proportionality in the narrow sense) and Alexy’s Weight Formula leads to the conclusion that this equation does not express (as it should) the role those laws have in constraining the range of choice presented by “prima facie discretion”. Coming from the problems therein detected, a new formula is presented; a formula that fully matches the substantive and the epistemic laws and that, to satisfy its function of internal justification of a balancing decision, only entails the variables those laws support.