Villios, S.Frantzis, C.2024-11-052024-11-052023Australian Tax Forum: a journal of taxation policy, law and reform, 2023; 38(3):377-4070812-695X0812-695Xhttps://hdl.handle.net/2440/143125This article was accepted for publication on 27 June 2023.The Australian Taxation Office (ATO) plays a crucial role in administering the complex tax laws of Australia. Its administrative function involves issuing guidance, such as taxation rulings, taxation determinations and practical compliance guidelines, to enhance certainty and fairness for taxpayers while promoting compliance. However, concerns have arisen about the ATO’s evolving role, with some claiming the ATO is overstepping its boundaries by assuming functions beyond its executive mandate. This article delves into the evolving role of the ATO and presents instances where it may be exceeding its executive responsibilities, by exercising judicial and legislative functions through the rulings system, increasingly resembling that of a “lore” and “law” maker. This article examines the complexities of the ATO’s role and how its expanding role poses challenges to the principles of the rule of law and the doctrine of the separation of powers. This underscores the need to strike a balance between the ATO’s executive functions and upholding the rule of law and the separation of powers for fair and efficient tax administration in Australia.enCopyright of Australian Tax Forum is the property of Tax Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use.Journal article2024-07-19701579Villios, S. [0000-0002-1568-0550]