## Facts

- Claudia Báez Sierra filed a nonmarital filiation/paternity action against Juliano Dinamarca Henríquez in the Fourth Civil Court of Arica.
- In the complaint, Báez Sierra alleged only that she had a relationship with Dinamarca Henríquez.
- She attached the child’s birth certificate to the complaint.
- The pleading included no further detail about circumstances supporting paternity (such as timing of conception or facts linking Dinamarca Henríquez to the child).
- Báez Sierra acknowledged in the complaint that Dinamarca Henríquez denied paternity.
- The trial court initially authorized service of process, then—on its own motion (ex proprio motu)—vacated that authorization and dismissed the complaint for insufficient factual allegations.
- Báez Sierra appealed; the court of appeals affirmed the dismissal.
- Báez Sierra sought review in the Supreme Court of Chile through a cassation appeal on the merits (casación en el fondo).

## Issues

1. Whether a nonmarital filiation complaint that alleges a relationship, attaches a birth certificate, and notes the alleged father’s denial can be rejected at the outset for lack of additional factual detail.
2. Whether the trial court may dismiss a filiation action on its own initiative at the pleading stage after initially allowing service of process.
3. How pleading rules should be applied in filiation litigation given the nature of the interests at stake in determining legal parentage.

## Decision

- The trial court dismissed the complaint ex officio after initially allowing service, reasoning that the complaint did not allege enough supporting facts.
- The court of appeals affirmed the dismissal.
- The Supreme Court of Chile (First Civil Chamber) granted cassation review and reversed the lower courts’ threshold dismissal.
- The Supreme Court set aside the dismissal and required that the action proceed through ordinary steps (including service and development of proof) rather than being terminated at filing based solely on sparseness of the allegations.

## Legal Principles

- Filiation/paternity actions are designed to permit judicial determination of parentage through a process that includes evidentiary development; courts should be cautious about ending such cases before that process occurs.
- Minimal allegations may be sufficient to open a filiation proceeding, even if the defendant denies paternity, because the truth of parentage is ordinarily resolved through evidence gathered after the case begins.
- A court’s authority to act on its own motion at the pleading stage is limited in party-driven civil procedure, and it does not extend to terminating a filiation claim simply because the initial narrative is brief.
- When a claim concerns legal identity and parentage, procedural rules should not be applied in a way that blocks access to a merits determination without allowing the evidentiary mechanisms contemplated for parentage disputes.

## Conclusion

Claudia Báez Sierra v. Dinamarca Henríquez addressed whether a thinly pleaded nonmarital paternity complaint could be dismissed sua sponte at the outset. After the trial court vacated its order authorizing service and dismissed the case for lack of detail—an outcome affirmed on appeal—the Supreme Court of Chile reversed on cassation and directed that the filiation action move forward so parentage could be tested through the ordinary litigation and proof-taking process rather than being barred at filing.


Claudia Báez Sierra v. v. Juliano Dinamarca Henríquez, Case No. 461-01 (2002)