Can Enforcement Backfire? Crime Displacement in the Context of Customs Reform in the Philippines
研究菲律宾海关改革对特定逃税手段的执法加强，发现虽然减少了目标逃税方式，但导致大量逃税行为转向其他方式（如通过免税出口加工区），总逃税量可能未减少，且转移程度与关税税率和进口量正相关。
Increased enforcement can lead crime to be displaced to alternative lawbreaking methods. In theory, crime displacement should respond positively to the size of profits threatened by enforcement. If enforcement displaces crime towards lawbreaking methods with lower variable costs, the overall crime rate need not fall. This paper examines a customs reform in the Philippines that raised enforcement against a specific method of avoiding import duties. The reform constituted a quasi-experiment: the increased enforcement applied only to shipments from a subset of countries, so that corresponding shipments from all other countries serve as a comparison group. Increased enforcement reduced the targeted method of duty avoidance, but led to substantial displacement to an alternative duty-avoidance method (shipping via duty-exempt export processing zones), amounting to 2.7 percent of total imports from treatment countries. The hypothesis that the reform led to zero change in total duty avoidance cannot be rejected. Displacement was greater for products with higher tariff rates and import volumes, consistent with the existence of fixed costs of switching to alternative duty-avoidance methods.