The principle of proportionality in biometrics:Case studies from Norway

The principle of proportionality is a decisive factor in the legal review of biometric systems by the Data Protection Authorities (DPA) in EU member states. However, in the working document on biometrics the Data Protection Working Party gives little guidance on how the purpose and proportionality principle must be applied to biometrics. There remain uncertainties as to the specific criteria and factors that are used for evaluating the proportionality of processing biometric information. This sometimes leads to contradictory decisions by different national DPAs on similar biometric related issues. This paper aims to discuss the legal factors and parameters that are generally adopted to address the proportionality issue in the biometric context. After a brief analysis of the legal notion of the principle of proportionality, the paper analyses and discusses the European organisations’ interpretation of the recent Norwegian cases on biometrics. The paper then concludes with a summary of the interpretation of the proportionality principle within the biometric context and gives specific recommendations of several important factors that need to be taken into account.