From 2015, migratory pressures put a heavy burden on EU countries. In 2015, Hungary took a new approach by building a border fence and creating criminal legal rules to protect it. This study aims to assess these measures in the EU sphere. Our research was based on EU (FRONTEX) and national (Prosecutor General’s Office information) data and assessed the Hungarian solution in the light of the migration policy of other Member States located along the main migratory routes. The data show: (1) the criminal law has no substantive effect, and (2) the law enforcement tools are effective. Moreover, the domestic data also show that Hungary is not consistent in its policy and has preferred law enforcement tools to criminal legal tools in the past few years, which violates the basic principles of criminal law: the principle of legality and the principle of ultima ratio.

Irregular migration has posed a persistent challenge to the European Union for decades, reaching a critical peak during the 2015–2016 migration crisis. In response, several Member States implemented physical border protection measures, including the construction of fences and barriers. This study investigates three core research questions: (1) whether the erection of border fences represents a unique phenomenon in Europe; (2) whether such measures are lawful under EU border protection law; and (3) whether they are effective in mitigating irregular migration. Drawing on time-series data from FRONTEX (2014–2025), the paper analyses trends in irregular border crossings and the evolution of physical border infrastructure across the EU. The findings indicate that border fences are not unprecedented in Europe, are legally permissible under current EU frameworks, and can serve as a legitimate, though not exclusive, tool for managing migratory flows. The study also explores conceptual distinctions between irregular and illegal migration and considers the instrumentalization of migration as a political tactic. While physical barriers may reduce pressure on specific border sections, their effectiveness is contingent upon broader geopolitical, legal, and humanitarian factors.