Catholic churches must justify why they continue to hold baptismal data, an opinion issued by the EU's top court has found, signaling that decades-old parish registers may not sit outside the reach of European data-protection law.

The opinion, delivered in a case now pending before the Court of Justice of the European Union (CJEU), addresses whether the Catholic Church can lawfully keep personal data recorded at baptism — typically a person's name, date of birth, parents' names and godparents — when the individual concerned no longer wishes to remain associated with the Church.

The court's opinion states that Catholic churches need to justify keeping baptismal data, putting the burden of demonstrating a valid legal basis for continued retention on the Church rather than on the individual demanding erasure.

What does the opinion actually say?

The opinion is non-binding. In the CJEU's procedural structure, an advocate general or, in this instance, the court issuing the opinion sets out a recommended reading of EU law, and the judges of the Court of Justice then deliver the final judgment. That judgment may follow the opinion in full, in part, or not at all.

According to the opinion, churches cannot simply assert an unlimited right to maintain baptismal registers. They must affirmatively justify retention of the data. The opinion's operative point is direct: Catholic churches need to justify keeping baptismal data.

The underlying dispute concerns individuals who have left the Church and object to their personal details remaining in parish records indefinitely. Baptismal registers have historically served the Church's own administrative and sacramental purposes, but the opinion suggests that tradition alone may not satisfy the justification requirements that EU data-protection rules impose on any organization processing personal data.

Who decided, and where?

The opinion comes from the Court of Justice of the European Union in Luxembourg, the body responsible for interpreting EU law uniformly across the member states. The case reference and the identity of the national court that referred the question were not specified in the report, but the procedural posture is the familiar one: a national court asked the CJEU to clarify how general EU data-protection principles apply to religious organizations.

The deciding body has not yet issued its final ruling. The opinion represents the recommended outcome; the judgment will follow in due course.

What does this change for practitioners?

For now, nothing is legally binding — but the direction of travel matters. Data-protection counsel advising religious organizations, dioceses and parishes across the EU should prepare for the likelihood that the final judgment will require churches to document a concrete justification for retaining baptismal records of persons who have asked for their removal or left the Church.

Practical steps for legal teams include:

• Reviewing how baptismal registers are maintained, in what format, and for how long.
• Identifying the legal basis the Church relies on for each category of data in the register.
• Preparing responses to erasure requests from former members that engage with the justification question rather than dismissing it.
• Assessing whether register entries can be annotated or partially restricted while preserving records the Church can genuinely justify.
• Monitoring the CJEU's incoming judgment, which will determine the binding standard across all 27 member states.

For lawyers acting for data subjects, the opinion strengthens the argument that leaving a religious community carries data-protection consequences, and that requests to delete or amend baptismal records deserve substantive answers.

Why does the timing matter?

The opinion lands as European regulators continue to test how far data-protection law reaches into long-standing institutional practices. Religious organizations have often treated their registers as internal, quasi-historical documents beyond commercial data-protection concerns. An opinion from the EU court requiring justification for keeping baptismal data pushes back on that assumption.

The final judgment will be the decision to watch. If the Court of Justice follows the opinion, Catholic churches — and potentially other religious bodies keeping comparable registers — will need a documented, case-specific rationale for every retention decision, at least where the data subject objects.

Until then, the opinion stands as a clear signal: the era of assuming ecclesiastical records are exempt from data-protection scrutiny is drawing to a close, and churches across the EU should be ready to answer the question the opinion poses — why, exactly, are you keeping this data?

Global Law Wire will report on the CJEU's final judgment when it issues.