The article examines the legal nature and practical implications of the classification of a pledge arising by operation of law from tax seizure. It is shown that the evolution of judicial practice has led to the recognition of such a pledge as having an autonomous place within the system of grounds for the creation of statutory pledges and to the extension to it of the legal effects traditionally associated with a conventional pledge, including priority in the satisfaction of the State’s claims. The article argues that the difficulties that have emerged in practice stem from the absence of a coherent regulatory model for the application of civil-law security devices within public-law relations. It concludes that this problem requires either the development within public law of distinct institutions for securing the performance of public obligations, or the introduction, at the level of the general provisions of civil legislation, of special rules defining the conditions for the use of security devices in the public sphere, their subject-matter framework, publicity requirements, and insolvency-related consequences.