An issue that often arises together with the liability to pay taxes levied on vehicles is the liability with respect to fines and sanctions. This is a sensitive field that traditionally remains in the realm of the powers of Member States. The case law of the Court has recognised that in the absence of Community legislation in the field of penalties for infringement of Community legislation, Member States are empowered to choose the penalties which seem appropriate to them.
However, the power of discretion is subject to the principle of proportionality. The Court[59] considered that criminal penalties are linked to the economic and social situation of the relevant Member State and that the application of criminal penalties to violations of vehicle registration rules cannot be considered per se an indication that penalties do not comply with the proportionality principle. The Court concluded that the question whether the penalties are disproportionate or proportionate was a matter to be assessed case-by-case and that the temporary immobilisation of a vehicle and release only upon payment of the fines might be disproportionate since it may deny the beneficiary the use of his vehicle. In that respect the Court has suggested that a solution more consistent with EU law could be to impose the provision of a security.
