The politics of mainland spouses in Taiwan

The recent expulsion of mainland China-born politician Li Chen-hsiu from Taiwan’s Legislative Yuan and the Taiwan People’s Party (TPP), along with the controversy surrounding her election and swearing-in as a legislator, reveals a deep contradiction within the political and constitutional order in Taiwan.

Taiwan’s constitutional framework is the Republic of China (ROC), which claims continuity with China. Yet under the Democratic Progressive Party (DPP) leadership, Taiwan increasingly defines itself in sharp opposition to anything associated with China.

Before Li’s expulsion, she was questioned by the ruling DPP establishment about her eligibility, as Taiwan’s laws require public office holders (including legislators) to renounce foreign citizenship.

There have long been ambiguities surrounding the legal status of individuals such as Li Chen-hsiu, the so-called “mainland spouses” (陆配), referring to mainland Chinese nationals who marry Taiwanese citizens and reside in Taiwan.

There are nearly 400,000 such “mainland spouses” in Taiwan today, who increasingly find themselves caught in an increasingly untenable situation amid rising tensions across the Taiwan Strait. They could acquire Taiwan/ROC’s household registration and passport after fulfilling the requirements stipulated in the Act Governing Relations between the People of the Taiwan Area and the Mainland Area. This law is distinct from the Nationality Law, which is applied to the naturalisation process of foreigners.

Before Li, there had already been several cases of mainland spouses serving in Taiwan’s public offices, mostly at the local level, and their eligibility had not been questioned until recently, when the DPP government under President Lai Ching-te began subjecting their legal status to stricter scrutiny and removed them from office for failing to comply with documentary requirements under the Nationality Law.

The use of the Nationality Law was a clear political message that people born in mainland China were to be treated legally as no different from other foreigners, rather than as a distinct category under the ROC framework, and this is an implicit rejection of the longstanding ambiguity that had allowed such individuals to occupy a liminal legal and political status.

Moreover, the Nationality Law requires naturalised individuals to provide official proof that they have renounced their original citizenship — something that is extremely difficult, if not practically impossible, for these mainland spouses. The People’s Republic of China government does not regard Taiwan as a foreign country, and local public security authorities responsible for handling such applications typically reject requests from mainland spouses residing in Taiwan.

Taiwan’s security concerns vis-à-vis Beijing are real and serious. But the extension of these concerns into the treatment of mainland spouses reflects a shift from targeted vigilance to broader social suspicion. The controversy surrounding Li’s eligibility for public office highlights this deepening climate of suspicion, driven by the DPP’s emphasis on Taiwanese identity.

Some mainland spouses do provocatively advocate for armed unification with mainland China and at least three of them were expelled. Nonetheless, others are subjected to mounting pressure as implicit judgments about their political loyalty intensify. The DPP’s project of identity consolidation, framing Taiwan as a distinct political and cultural entity separate from China, has been both a reflection of public sentiment and a driver of it. In practice, this project has often relied on sharpening internal distinctions, particularly when it comes to cross-strait identities.

Mainland spouses, in this context, become politically useful symbols. Debates over their rights can be framed as matters of national security, allowing broader anxieties about China to be expressed through domestic policy. Li Chen-hsiu’s case became one such focal point. While her expulsion had immediate political causes, the intensity of the reaction cannot be separated from the broader climate in which mainland identity is increasingly politicised.

What makes this trajectory particularly fraught is that it exposes a structural tension at the heart of Taiwan’s political and constitutional order, one that cannot be easily resolved through administrative tightening or legal reinterpretation. The existing framework, by design, leaves open the question of how people from mainland China are to be categorised: neither fully foreign nor fully domestic. For decades, this ambiguity provided a degree of flexibility, allowing cross-strait social interactions to proceed without forcing a definitive political settlement. The recent shift toward stricter legal classification, however, signals a diminishing tolerance for such ambiguity.

In narrowing this space, there is the risk of conflating legitimate security concerns with broader questions of identity and belonging. When suspicion expands to encompass an entire social category, defined not by actions but by origin, it begins to erode the normative foundations of a democratic polity. Legal regimes that hinge on proving political loyalty, especially when the criteria remain implicit or unevenly applied, can produce uncertainty not only for those directly affected but also for society at large.

At the same time, the pressures driving this shift are not difficult to understand. Intensifying cross-strait tensions, growing military threats and sustained political pressure from Beijing have reshaped the boundaries of what is considered acceptable risk. In this environment, policies that once seemed unnecessarily rigid may now appear prudent. Yet prudence in the security domain does not automatically translate into coherence in the legal or constitutional domain. The more Taiwan defines itself in opposition to China, the more strain it places on a constitutional framework that still formally claims continuity with it.

Li Chen-hsiu’s case thus points beyond the immediate controversy to a deeper question: whether Taiwan can sustain a political and legal order that continues to accommodate ambiguity while responding to present-day geopolitical pressures. Contrary to the view that such ambiguity is inherently unstable, it may in fact be a necessary feature of Taiwan’s constitutional and social reality.

The ROK framework has long functioned not by resolving the question of identity and sovereignty in definitive terms, but by managing it through layered and sometimes deliberately imprecise arrangements. This flexibility has enabled Taiwan to integrate diverse populations, including those from mainland China, without forcing rigid and potentially destabilising classifications. Maintaining such calibrated ambiguity also keeps open the political and interpretive space required for managing cross-strait relations.

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