Should the EU open its doors to neighbouring countries? This is the question that many pose as Ukraine seems to be the next in line to join the Union. Since EU enlargement has returned to the fray, it is of the utmost importance that its accession model is reviewed. The current system revolves around the Copenhagen criteria that compels a candidate country to respect and implement judicial, institutional, economic and bureaucratic reforms in order to adhere to precise democratic standards. Once these reforms are achieved and considered credible by the European Commission, all the Member States’ parliaments need to approve and ratify the accession. An observation made by many scholars is that the position of the European Union during the accession period is characterized by an asymmetry: strong and effective during the pre-accession phase, yet remarkably weak once full membership is granted. Notably, there have been many cases in which a country backslided and implemented undemocratic reforms that led to the erosion of the rule of law. From a legal standpoint, the European Union lacks a clear mandate to intervene.

A case study that shows this dynamic is the Hungary of Viktor Orbán. Hungary joined the European Union in the 2004 enlargement as an example of post-Soviet democratization, but it changed trajectory with the electoral win of Fidesz in 2010. With a two-third majority in parliament, Orbán monopolized information through KESMA, a pro-government enterprise that controls 470 media outlets, influenced the Constitutional Court by anticipating the retiring age and appointing like-minded judges, implemented a gerrymandering electoral law, that allowed Fidesz to achieve 67% of seats with 44.5% of the popular vote in 2014, and invested European funds as a patronage that enriched his friends, family and protected its political interest. Not only did Orbán erode the rule of law of Hungary, but he also utilized its veto-power on key European decisions, such as sending support packages to Ukraine and sanctioning Russia, as an extortion tool to unfreeze EU funds.

In front of these infractions, the EU has a wide set of tools to limit and punish these behaviours. An infringement procedure can be undertaken for countries that violate EU laws, the Rule of Law Conditionality Mechanism allows Member States to suspend EU funds to a country with a qualified majority as it happened for Hungary in 2022 and the Article 7 procedure, often regarded as the “nuclear option”, which theoretically allows for a Member States’ suspension of voting rights. However, the practical application of these instruments remains inefficient. Article 7 needs unanimity to be adopted making it easier for countries who violate EU laws to ally themselves, and infringement procedures are often narrow and incapable of tackling democratic erosion. On the contrary, the Rule of Law Conditionality mechanism, implemented in 2020, proved to be an efficient instrument to freeze EU funds in case of democratic backsliding, as it requires a qualified majority instead of unanimity. Nevertheless, this tool only has economic and financial consequences, making it challenging to politically constrain a country to reverse its decisions.

The above-mentioned limitations of after-accession measures to counter democratic backsliding prove a paradox: while the European Union is capable of withholding funds, it cannot prevent a country from holding the EU’s foreign policy hostage, as revoking the veto power is an unattainable goal. In the context of a future enlargement, these structural flaws in the accession system need to be addressed. Hence, a few policy recommendations: first is a staged accession which substitutes the current “all or nothing” system with a phased process, in which candidate States get gradual access to the Single Market and funds based on their level of reforms. It may an advantageous compromise both for the European Union, as it can revoke every achievement as soon as backsliding happens, and for candidate States, that will not have to wait years to see the benefits of joining the EU. Additionally, what may be helpful could be an extended post-accession monitoring from 3 to 10 years of post-accession monitoring. By reforming article 2 of the Treaty of the European Union, the European Commission will be able to withhold funds with a qualified majority instead of using article 7 that involves unanimity. Moreover, a ten-year span allows experts to monitor two legislative cycles and effectively assess whether or not reforms are stable and functioning. Finally, the EU must reform its decision-making architecture by replacing the unanimity requirement with Qualified Majority Voting in the European Council, particularly regarding foreign policy decisions and rule-of-law enforcement mechanisms. Eliminating unanimity would neutralize a backsliding state’s ability to leverage its veto power for political extortion or form protective alliances to shield illiberal partners. Transitioning to QMV is therefore a vital prerequisite to ensure that future enlargement does not compromise the Union's operational capacity or democratic integrity.

In conclusion, expanding the European Union to Ukraine and the Balkans is a geopolitical imperative that cannot be delayed. However, enlargement must not come at the expense of EU’s values and principles. As demonstrated, financial and economic penalties are not sufficient to prevent democratic backsliding or foreign policy paralysis. By implementing a staged accession, extending post-accession monitoring and replacing unanimity with QMV, the European Union can address the accession asymmetry. Reforming the current enlargement system is what will decide whether future expansions strengthen or dilute the democratic integrity of the European Union.