Nearly half of all civil divorces in Singapore last year relied on unreasonable behaviour as the grounds for marital dissolution, making it the dominant reason couples formally end their unions. Data released by the Department of Statistics on July 10 revealed that 48.7 per cent of non-Muslim divorces in 2025 invoked this ground, a striking contrast to adultery, which appeared in just 0.9 per cent of cases. The figures tell a revealing story not merely about relationship breakdown, but about the structural differences between Singapore's civil and Muslim divorce regimes, and the practical calculus that guides couples when navigating the family courts.
Muslim divorces present a markedly different landscape. Among couples dissolving marriages under Muslim law, infidelity emerges as the second most frequently cited "main issue," accounting for 18.4 per cent of cases, trailing only personality differences at 21.5 per cent. This twenty-fold disparity between civil and Muslim divorce statistics has prompted legal observers to dig deeper into the institutional and procedural frameworks that produce such divergent patterns. The gap, lawyers argue, reflects not actual differences in adultery prevalence between religious communities, but rather how each legal system is structured to recognise, define, and require proof of marital breakdown.
The civil divorce regime operates under the Women's Charter, which establishes a single legal ground—irretrievable breakdown of marriage—that can be proven through six distinct pathways. Three of these are fault-based: adultery, desertion, and unreasonable behaviour. Two others are non-fault mechanisms that turn on separation: three years with mutual consent, or four years without it. The sixth route, divorce by mutual agreement, was introduced as recently as July 1, 2024, and immediately captured the third-largest share of civil divorces filed in 2025. This menu of options has fundamentally shaped how divorcing couples construct their cases, pushing many away from fault-based grounds that require intensive proof and toward alternatives that resolve matters more efficiently.
The Muslim divorce system, governed by the Administration of Muslim Law Act and adjudicated in the Syariah Court, operates on different principles entirely. Unlike the Women's Charter, AMLA does not enumerate statutory facts that must be proven. Instead, the Syariah Court applies AMLA and relevant principles of Muslim law to determine each case on its merits. This distinction proves critical: Muslim divorce statistics record the "main issue" that parties themselves identify as causing breakdown, whereas civil divorces require parties to prove specific legal facts before a judge. The divergence is not one of substance but of measurement—one system documents the reasons people give for divorce, while the other documents legal facts that have been judicially established.
Proving adultery in civil divorce proceedings presents formidable practical obstacles that discourage its pursuit. Family lawyers report that the process demands compelling circumstantial evidence: private investigator reports, photographs, videos, or other documentation of infidelity. These investigations are expensive, time-consuming, and often unnecessary given alternative grounds. A spouse seeking to dissolve a marriage due to infidelity can instead invoke unreasonable behaviour, which encompasses extramarital affairs but requires no proof of sexual contact. The shift from adultery to unreasonable behaviour also reduces acrimony. Rather than forcing a detailed courtroom reconstruction of infidelity, parties can present their spouse's conduct more broadly, a characterisation less likely to provoke bitter contestation or revenge.
Unreasonable behaviour operates as a catch-all ground that captures an expansive range of conduct damaging to marriage. It encompasses family violence, verbal abuse, controlling patterns, substance addiction, compulsive gambling, financial mismanagement, parental neglect, and yes, extramarital affairs. This capacious definition means that most circumstances precipitating divorce can plausibly be characterised as unreasonable behaviour. In uncontested cases, detailed documentary proof often becomes unnecessary because both parties acknowledge the allegations. Contested cases do require evidence—text messages, bank records, police reports, medical documentation, or testimony from neighbours, relatives, and counsellors—but the threshold remains more flexible than the exacting standard applied to adultery.
The practical advantages of unreasonable behaviour explain its dominance in civil divorce filings. Compared with adultery, it is simpler to establish and requires no waiting period. Couples seeking to invoke the three-year separation ground with consent must remain apart for that entire duration before filing, as must those invoking the four-year separation route without consent. Unreasonable behaviour permits immediate filing regardless of cohabitation status, a significant advantage for spouses determined to exit a deteriorating marriage promptly. For those not seeking fault-based grounds, the waiting periods imposed by separation-based pathways represent substantial delays, making unreasonable behaviour an attractive middle ground.
The introduction of divorce by mutual agreement in mid-2024 has begun reshaping the divorce landscape. This mechanism eliminates the "blame game" that characterises fault-based proceedings, allowing couples to dissolve marriage by joint agreement without rehearsing grievances or establishing fault. Its rapid uptake—it became the third most commonly cited fact in 2025—signals growing appetite among divorcing couples for less adversarial processes. The mutual agreement route appeals particularly to those capable of cooperative negotiation and those seeking to protect children from the collateral damage of contested proceedings.
Legal experts caution against misinterpreting the statistics to suggest that adultery is substantially more prevalent among Muslim couples than civil divorcing couples. The numbers instead reflect how differently the two systems measure and categorise marital breakdown. Muslim divorce statistics capture parties' own characterisations of their situation, while civil divorce statistics record legal facts proven in court. The two metrics are not comparable—one is subjective reporting, the other judicial determination. Inferring actual behaviour patterns from this data conflates distinct methodologies and risks perpetuating stereotypes unsupported by the underlying evidence.
The framework differences also illuminate broader patterns in how divorcing couples strategically navigate law. The existence of multiple grounds permits selection among them based on practical and emotional considerations. A spouse whose marriage has fractured due to infidelity might reasonably calculate that alleging unreasonable behaviour—broader, less requiring of detective work, and less humiliating—serves their interests better than insisting on adultery. This rational choice-making at scale produces the statistical distributions we observe: not accurate reflections of what actually destroyed marriages, but rather accurate reflections of how couples instrumentalise available legal grounds.
For Malaysian observers, Singapore's experience offers instructive contrast. Malaysia's family law operates through multiple parallel systems—civil courts applying the Law Reform (Marriage and Divorce) Act for non-Muslim couples, and state-level Syariah courts for Muslims—creating similar possibilities for comparative institutional analysis. The practical dominance of particular grounds in any jurisdiction owes less to underlying behaviour patterns than to how legal frameworks incentivise different strategic choices. Understanding this distinction becomes crucial when policymakers debate reforms, as statistics on cited grounds can mislead if interpreted as direct windows into marital behaviour rather than as institutional outputs shaped by procedural architecture.
