Misdemeanour and misdemeanour proceedings are stipulated only for those human activities that breach or threaten public policy, social discipline and social values that are guaranteed and protected by The Constitution of the Republic of Croatia, international law and legislation, protection of which is not possible without misdemeanour sanctioning and is not enforced through criminal justice coercion. Within Croatian justice system, misdemeanour law is usually considered as part of the criminal law in a broader sense, but it is regulated by Law on Misdemeanours. Therefore it is necessary to emphasise that also in the field of misdemeanour law the principle of „No crime, no punishment without law“ (lat.nullum crimen, nulla poena sine lege) applies. Subsequently, Law on Misdemeanours prescribes that misdemeanours and misdemeanour sanctions can be prescribed by law as well as decrees of municipalities and regional administrations, based on power given to them by the Constitution and the state laws which may not be transferred. Provisions of the Law on Misdemeanours prescribe that administrative body of The City of Rijeka have an authorisation for monitoring the implementation of the City Council’s decrees as well as implementation of provisions that are established by other regulations and, ultimately, conduction of misdemeanour proceedings. Municipal police officers and traffic wardens, as officials of the administrative body of The City of Rijeka, in everyday work issue Mandatory misdemeanour order as the main instrument for misdemeanour sanctioning of offenders. Proceeds and provisionally cashed fines are being recorded as City’s budget revenue, free to be disposed of.