The use of third-party information reporting for tax deductions: evidence and implications from charitable deductions in Denmark
研究了丹麦2008年引入慈善捐赠信息报告后，抵扣申报数量翻倍、总额增长15%，主要源于此前未申报的抵扣，反驳了逃税是主要问题的假设，并发现审计高估了逃税程度。
We show that the introduction of information reporting for charitable tax deductions in Denmark in 2008 was associated with a doubling in the number of deductions claimed, and a 15% rise in the total value of claims, which can be credibly attributed to previously unclaimed deductions. This contradicts the presumption that evasion is the main source of non-compliance for deductions, and that the use of information reporting raises revenue collections. A pre-reform randomized audit experiment did not detect the unclaimed deductions, implying audits overstate evasion relative to extensive-margin underreporting. Various tests suggest that compliance cost, passive choice and overwithholding suppressed self-reporting of deductions.