Hague Convention and child custody: whoever files first holds the forum

A mother travelled with her five-year-old son from Denmark to Prague without the father's consent and filed a child custody petition here. The Danish court meanwhile ran its own proceedings, granted the father temporary sole custody and later asked the Czech courts to take over the case. The District Court for Prague 9 refused, discontinued the custody proceedings — and the Czech Supreme Court upheld that approach. The key is the Hague Convention on Parental Responsibility and Measures for the Protection of Children (published in the Czech Collection of International Treaties under No. 141/2001) and its lis pendens rule: whoever is first with proceedings before a court that has jurisdiction at that moment "holds the forum", even if the child later physically moves elsewhere.

Decision Case No. 24 Cdo 1207/2026 of 27 August 2026 is fundamental for families living across two countries. It clarifies three contested questions that had no clear answer in Czech case law — and shows that the tactical question of "where to file first" can matter more than arguments about where the child has a better home. For clients dealing with child custody after separating from a partner living abroad, this becomes the first question to resolve before any specific arrangements are even discussed.

A family divided between two states

The facts are, unfortunately, typical. The family lived in Prague until 2022, when the mother, with the father's consent, moved with the child to Denmark. The parents concluded an out-of-court custody agreement there and, in May 2023, an agreement on the father's contact with the child before the competent Danish family court. The boy attended nursery school in Denmark.

In November 2023 the mother travelled back to the Czech Republic with the child — this time without the father's consent. Her reason was a suspicion that the father was sexually abusing the son. The father reacted immediately: on 14 November 2023 he applied to the Danish Agency of Family Law for the child to be placed in his care. In less than a month he was granted temporary sole custody, and in February 2024 the competent Danish family court confirmed that decision.

Through the Office for International Legal Protection of Children (ÚMPOD), the father also applied for the child's return under the Convention on the Civil Aspects of International Child Abduction. He later withdrew that application, so return proceedings never started. He has not seen his son since autumn 2023 and has not paid maintenance since January 2024. The mother meanwhile filed custody petitions in the Czech Republic — the first in November 2023 (discontinued for lack of international jurisdiction), the second in 2025. The decision described here concerns the second set of proceedings.

In April 2025 the Danish court, relying on Article 8 of the Convention, asked the Czech courts to assume jurisdiction. Its reasoning was practical: the mother is the primary carer, the child is five years old and has not seen his father since autumn 2023, and the Danish authorities admit they have no way of obtaining information about his current life with the mother. The Danish court nevertheless continues to regard the mother's departure with the child as a wrongful removal. The District Court for Prague 9 still declined to take over jurisdiction. It noted that the Danish authorities have known the family since February 2023, mediated the parents' agreement and are conducting proceedings on enforcement of the contact order and on the father's custody application, in which they issued an interim decision. In the district court's view, the Danish proceedings were further advanced and the Czech courts would not be better placed to assess the child's best interests; the Danish authorities can obtain information about the mother's circumstances through a request via ÚMPOD. At the same time it discontinued the custody proceedings, holding that Czech jurisdiction was barred by lis pendens under Article 13 of the Convention. The Municipal Court in Prague upheld the discontinuance as regards custody (it severed maintenance and did not discontinue the proceedings in that part; the appeal on a point of law no longer concerned it).

What the Hague Convention actually says about lis pendens

The Convention's system prevents the authorities of two Contracting States from deciding the same matter at the same time. This is the role of Article 13 — the counterpart of the domestic bar of pending proceedings. Proceedings started later must be discontinued if, at the time they were started, proceedings on the same subject matter were already pending before the authorities of another Contracting State and those authorities had jurisdiction when "their" proceedings were started. The only exception is where the authorities of the original state decline jurisdiction (Article 13(2) of the Convention). The lis pendens effect is tied to the subject matter of the proceedings, so it does not prevent the authorities of the new state from deciding issues on which no proceedings are pending in the original state. That is precisely why the Czech courts could continue the maintenance proceedings, but not the custody proceedings.

What matters is the point in time at which jurisdiction is assessed. The appellant argued that jurisdiction of the Danish courts may in the meantime have shifted to the Czech Republic, where the child had acquired a new habitual residence, so that there were no longer two legitimate fora. The Supreme Court rejected that reasoning. For the lis pendens effect it is sufficient that the authorities conducting the earlier proceedings had jurisdiction when the application was filed with them. A later transfer of jurisdiction through a change in the child's habitual residence does not alter that effect — only the situation at the moment the earlier proceedings were started is decisive.

This is where the greatest practical consequence lies. Whoever starts proceedings first, having jurisdiction under Articles 5 to 10 of the Convention at that moment, holds the forum. It does not matter that the child has meanwhile settled elsewhere, attends nursery there and has friends and wider family there. The argument that "the court in the new state has better access to information about the child" does not in itself overcome the lis pendens bar. The Supreme Court chose a rule that is simple to apply and reduces room for speculation: what counts is the order of filing and jurisdiction at the moment proceedings were started, not how things develop between the start of proceedings and the decision on the bar.

Why Article 7 creates no exception to the priority rule

The mother tried to get around Article 13 through Article 7 of the Convention. In cases of wrongful removal of a child, Article 7 keeps jurisdiction with the state of the child's former habitual residence until specific conditions are met — including that the parent with custody rights has not requested the child's return. The father did apply for return but later withdrew the application and no return proceedings took place. According to the appellant, the situation should therefore be treated as if no request had ever been made — and jurisdiction should pass to the Czech Republic. The argument went further: Article 7 was supposedly a preliminary question to Article 13, because without clarity on who actually had jurisdiction at the relevant time, the priority rule should not apply at all.

The Supreme Court, however, shows that Articles 7 and 13 address different problems. Article 7 determines where jurisdiction lies in a child abduction case — its purpose is to preserve the jurisdiction of the state of former habitual residence even where, in the normal course of events, it would pass to the state of the new residence. Article 13 deals with the situation where the authorities of several states hypothetically have jurisdiction at the same time, and provides that whoever came first decides. There is therefore no relationship of preliminary question, as the appellant claimed. Any transfer of jurisdiction during the Danish proceedings — whether under Article 5, Article 7 or another provision — does not affect their lis pendens effect.

The Convention does allow jurisdiction to shift during proceedings, but it does not specify how each state should verify this procedurally or what procedural consequences the loss of jurisdiction has; the Contracting States deal with this in their own way. That is exactly why the Convention opted for a simple solution: the later authority may decide the matter only once the earlier proceedings in the other state have demonstrably ended. It is not enough for it to take the view that the first state has already lost jurisdiction. Otherwise the risk of conflicting decisions in two countries would be enormous — which is precisely what the Convention is meant to prevent. Whether the withdrawal of the return application changes the father's position under Article 7(1)(b) did not need to be examined in detail: even if jurisdiction had shifted, the Danish proceedings would have kept their priority under Article 13.

The child's best interests as a guide, not a trump card

The mother's third argument sounded natural: interpretation must take into account the best interests of a child who actually lives in Prague, attends nursery here and has not seen his father for two years. Is it not absurd for a foreign court, which itself asked to transfer the case and admits it struggles to obtain information, to decide about him? The Czech Children's Ombudsman, who was allowed to comment as amicus curiae, leaned towards the same line of argument. ÚMPOD, as the child's guardian, on the other hand briefly supported the appellate court's conclusion that the pending Danish proceedings barred a Czech decision.

The Supreme Court does not avoid this argument but places it within the Convention's system. The child's best interests are a guide for interpreting the Convention, not a universal key for bypassing its clear rules. It is precisely predictability — whoever is first before the competent court holds the forum — that protects the child from becoming the centre of a cross-border tug-of-war between courts, in which a party that fails in country A moves the child to country B and tries again. That is exactly what Article 13 prevents. If a court reopened in every such case the question of where the child currently has stronger ties, the Convention would become an invitation to procedural forum shopping.

Articles 8 and 9 of the Convention are a different matter: they allow jurisdiction to be transferred between courts by agreement. The Danish court initiated such a transfer and the Czech court refused it. Had it accepted, the situation would be different — jurisdiction would have passed, the Danish proceedings would have ended and the Czech proceedings could have continued. However, the district court concluded that the Danish court was better placed to decide because it has known the family from the start, has ongoing proceedings and can obtain information about the mother's circumstances by request. The Supreme Court does not revisit that assessment, which is the district court's discretion in the specific case. For the parties this means that a dispute over the transfer of jurisdiction is a matter of mutual judicial discretion, not of entitlement: there is no procedural right to compel a Czech court to assume jurisdiction if it does not wish to.

Practical takeaways for cross-border child custody

For families where one parent lives or works abroad, the decision has several concrete implications. First, the moment proceedings are started carries strategic weight. If a separation is looming and the children have ties to two states, the question of where and when to file a custody petition is no formality. Whoever is first before the competent court holds the forum, even if circumstances later change. A difference of a few weeks can decide which legal system and which judicial culture will accompany the child for years to come.

Second, moving a child to another state without the other parent's consent does not pay off even from a purely procedural point of view. Even if the child settles into the new environment and acquires habitual residence there, proceedings started in the state of former residence retain their lis pendens effect. Not even the best-interests argument overrides the priority rule. On top of that comes the risk that the other parent and the foreign court will classify the removal as wrongful, with all the consequences the Hague Child Abduction Convention attaches to that classification.

Third, once parallel proceedings arise, the only way to consolidate them is the procedure under Article 8 or 9 of the Convention, i.e. an agreement between courts on transferring jurisdiction. That requires active procedural work and cooperation with the Office for International Legal Protection of Children. Relying on the later court to find on its own that the earlier court's jurisdiction has lapsed does not work. And if a Czech court refuses a request to assume jurisdiction, there is no remedy against that communication — the Supreme Court confirmed that it is the final handling of a foreign court's request, not a resolution that a party could challenge by appeal.

We handle such situations within our Family and Inheritance Law practice, and experience confirms that the first consultation with a lawyer should take place before one parent leaves with the child across the border. Later remedies — whether return proceedings or an attempt to move the forum to the state of new residence — are always more demanding and less certain than a correctly chosen first step. Whether you are dealing with divorce, the separation of unmarried parents or child custody after a break-up, the key decision is made earlier than people usually realise. And if your family already lives across borders, it is worth having a scenario ready in case relations between the parents deteriorate — including clarity on where the child's habitual residence currently is and which courts would have jurisdiction in a dispute.

Source: Resolution of the Supreme Court of the Czech Republic, Case No. 24 Cdo 1207/2026 of 27 August 2026, published on profipravo.cz on 16 September 2026.