Opposition to acquisition (oposição) — control layer (Art 9, Art 10)

PT-XCT-02 documents the oposição à aquisição por efeito da vontade mechanism — the Ministério Público's power to oppose the consolidation of nationality acquired by voluntary declaration (marriage, união de facto, adoption — all Section I "by will" routes). This is not an acquisition route for applicants; it is a control layer operated by the State through the Ministério Público (MP) that can prevent nationality from consolidating after a declaração de vontade has been filed.

Opposition is distinct from Art 8 loss: a successful Art 9 opposition means the nationality never validly consolidated (the acquisition is void ab initio), whereas Art 8 renunciation operates prospectively against an already-held nationality.

LO 1/2026 (EIF 19-05-2026) reformed the oposição mechanism in important respects: it replaced the vague "comportamentos" opposition ground with a more specific yardstick tied to Art 6(1)(c)-(i), and it struck a portion of the former Art 9(1)(a) second part as constitutionally infirm (TC Ac. 1133/2025, Proc. 1383/2025). The 2-year MP opposition window and the safe-harbour provisions remain.

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PT-XCT-02 is not an applicant route. No person "applies" to trigger it. Instead, it governs when and how the Ministério Público may act to prevent consolidation of a nationality acquired by will.

Triggering context: Opposition can only be raised against acquisition by will under Section I of Lei 37/81 — specifically:

• Art 3(1): acquisition via marriage (PT-MAR-01).
• Art 3(3): acquisition via união de facto after judicial recognition (PT-MAR-02).
• Art 5: acquisition via adoption by a Portuguese national (PT-ADP-01, mandatory declaração de vontade since LO 1/2026).

Opposition does NOT apply to:

• Jus sanguinis attribution under Art 1 (originária, automatic or by declaration).
• Naturalisation under Art 6 (the MP's role there is as part of the substantive eligibility assessment, not the oposição regime).
• Art 8 loss or Art 4 reacquisition.

Opposition ground (W7 redaction, Art 9(1)(a), first part): Inexistência de laços de efetiva ligação à comunidade nacional — absence of effective community links. The yardstick for assessing this is now expressly tied to Art 6(1)(c)-(i), meaning the MP assesses: language and Portuguese culture/history/symbols (c); civic/political knowledge (d); adherence to democratic rule-of-law principles (e); absence of conviction to effective imprisonment exceeding 3 years for enumerated offences (f) — rebuttable presumption per Art 6(14); no security threat (g); no UN/EU restrictive measures (h); capacity to ensure subsistence (i). The former Art 9(1)(b)/(d) grounds (generic "comportamentos") were revoked by LO 1/2026.

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1. Within the window: The opposition action must be brought within 2 years of registration of the nationality acquisition (Art 10(1) Lei 37/81). The anchor event is the filing of the declaração de vontade (not the RNP registration date — per TC Ac. 768/2024 + Ac. 522/2025, Art 56(1) RNP anchoring from registration date is illegal).

2. No safe-harbour applies: Art 9(2) Lei 37/81 bars opposition (except on Art 6(1)(f)-(h) criminal/security/sanctions grounds) when:

• The marriage or união de facto exceeds 6 years at the time the opposition would be raised; OR
• There are common children holding Portuguese nationality. The safe-harbour does NOT apply to the Art 5 adoption route (where only the effective-links assessment remains without a time-based harbour).

3. Substantive ground: The MP must demonstrate, on the Art 6(1)(c)-(i) yardstick, that the acquirer lacks effective community links. Automatic opposition based solely on a criminal conviction is unconstitutional (TC line from Ac. 331/2016 through Ac. 846/2023); the conviction bars in Art 6(1)(f) may support the opposition only as a rebuttable presumption subject to individual proportionality assessment.

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Initiation: The MP receives notice of registered nationality acquisitions and may initiate opposition within the 2-year Art 10(1) window.

Forum: Opposition proceedings are heard before the competent administrative court (Tribunal Administrativo e Fiscal). Appeals route to the Supremo Tribunal Administrativo (STA). Proceedings are governed by the Código de Processo nos Tribunais Administrativos (CPTA).

Outcome of successful opposition: The acquisition is void ab initio — the person is treated as never having acquired Portuguese nationality via the opposed route. This is distinct from Art 8 loss (which operates prospectively and presupposes a validly held nationality).

Outcome of failed opposition: The nationality consolidates; no further Art 9 opposition on the same facts is possible.

Regulamento deadline rule (Art 56(1) RNP): Following TC Ac. 768/2024 and Ac. 522/2025, the provision of the Regulamento (DL 237-A/2006 in the DL 26/2022 redaction) that set the 2-year counter from the RNP registration date is illegal. The operative counter runs from the declaração de vontade (the "fact on which acquisition depends" per Art 10(1)). Until the pending Regulamento update (~16 August 2026) reflects this correction, practitioners should rely on Art 10(1) Lei 37/81 directly, not on Art 56(1) RNP.

TC Ac. 768/2024 + Ac. 522/2025 scope clarification: These decisions concern the opposition-deadline timeline provision in Art 56(1) RNP only. They do NOT concern the Sephardic Art 24-A effective-connection requirement (PT-ASSERT-HIS-009), despite arising from the same DL 26/2022 Regulamento amendment. Conflating the two decisions is a known error pattern.

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• Lei 37/81 Art 9 (oposição) — LO 1/2026 redaction: sets opposition grounds and safe-harbour conditions.
• Lei 37/81 Art 10(1) (opposition window) — 2 years from registration of the relevant acquisition fact.
• Regulamento da Nacionalidade DL 237-A/2006, Art 56 (opposition deadline rule) — partially struck as illegal (see below).

Constitutional backdrop:

• CRP Art 30(4): "Nenhuma pena envolve como efeito necessário a perda de quaisquer direitos civis, profissionais ou políticos" — automatic-effect prohibition, applied by TC to bar automatic conviction-based opposition.
• CRP Art 164(f): nationality acquisition/loss/reacquisition is the exclusive non-delegable competence of the AR exercised by organic law; regulations cannot add conditions not found in Lei 37/81.
• CRP Arts 18(2), 26(1): proportionality and dignity, applied to nationality opposition criteria.

Key TC jurisprudence reforming the opposition regime:

• TC Ac. 331/2016 (Proc. 1155/2014, 19-05-2016): automatic conviction-based opposition (Art 9(b) + Art 56(2)(b) RNP) unconstitutional — Art 30(4) CRP.
• TC Ac. 534/2021: same bar applied where conviction followed by suspended sentence under CP Art 43.
• TC Ac. 127/2023 (Proc. 720/2022): criminal-conviction bar must weigh extinction of criminal record, rehabilitation, time elapsed, and circumstances individually; no automatic bar.
• TC Ac. 846/2023: reiterated Art 9(b) + Art 56(2)(b) RNP unconstitutional; cited Ac. 331/2016 + 534/2021.
• TC Ac. 1133/2025 (Proc. 1383/2025, Plenário, 15-12-2025, DR Série I n.º 2, 05-01-2026): struck Art 9(1)(a) second part of Decreto AR 17/XVII (the "ostensiva rejection" language) as constitutionally indeterminate (Art 2 + Art 164(f) CRP). The first part of Art 9(1)(a) — opposition on the ground of inexistência de laços de efetiva ligação — survived and was carried into LO 1/2026 with the Art 6(1)(c)-(i) yardstick.
• TC Ac. 768/2024 (generalised by Ac. 522/2025, 17-06-2025, DR Série I n.º 140, 23-07-2025): Art 56(1) of DL 237-A/2006 (in the DL 26/2022 redaction) is ILLEGAL. The regulation set the opposition-action time-limit from the RNP registration date, contradicting Art 10(1) Lei 37/81 which anchors it to "the fact on which acquisition depends" (the declaração de vontade). A regulation cannot override an organic law.
• STA Proc. 0219/10 (0219/10.6BEPRT, 1.ª Secção, 14-02-2019): the administration cannot read an unlegislated "portugueses de origem"-only condition into the nationality law — that would add an acquisition condition reserved to the AR under CRP Art 164(f).

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