Unobscuring the Concept of Tax Morale: A Systematic Review of the Literature

Abstract Enhancing tax morale is considered crucial for increasing tax compliance, reducing tax evasion, and decreasing the shadow economy. Despite its clear importance within tax research and policy development, there is surprisingly little consensus about what tax morale is. To address this problem, a systematic literature review of 323 articles was conducted. The review summarizes the many different definitions and operationalizations of tax morale, revealing substantial heterogeneity in both. Definitions range from relatively narrow (e.g., intrinsic motivation) to extremely broad (e.g., umbrella term for nonpecuniary motivations). The review identified 91 different operationalizations, 72 of which were used only once. Importantly, the prevailing definitions and operationalizations of tax morale exhibit a lack of alignment, often within the same article. The most common definition is the intrinsic motivation to pay taxes. In contrast, the most common operationalization is a single question about the justifiability of cheating on taxes. The review emphasizes the need to establish a broad-based consensus on the definition of tax morale. It outlines initial steps for developing an operationalization that aligns with this potential definition. It is recommended that, as a first-step solution, researchers be more specific and provide more detail when they use the term tax morale. In the interim, this will promote cumulative knowledge generation and, in time, a more precise definition of tax morale to underpin relevant policy implications.