Although England and Wales has a discretionary financial system on divorce giving Judges power to consider what is fair, issues of jurisdiction are binary – a win/lose outcome: you either have it or you don't. It sounds simple, but if there is a dispute about it, securing jurisdiction can be a complex, lengthy and expensive process.
Who can file in England
To file a divorce petition in England, an applicant has to show either:
- that at least one of the criteria in Article 3 of the Council Regulation (EC) No 2201/2003 known as 'Brussels II bis' applies (set out below); or
- that no other EU member state has jurisdiction, and one of the parties is domiciled in England & Wales.
Brussels II bis currently applies to all member states (except Denmark), and for the purposes of the regulation, England & Wales, Scotland, Northern Ireland and Jersey are considered as separate, but related jurisdictions.
Habitual residence and domicile
Habitual residence turns on where someone's 'centre of interests' is, taking into account all relevant circumstances linking you to a place, both subjective and objective. You cannot be habitually resident in two countries at the same time and it is not just a question of how long you have been there.
Confusingly, the term 'domicile' in civil jurisdictions means habitual residence, but in England and Wales, domicile relates to where someone considers their home to be even if they may reside elsewhere. An individual takes his or her father's domicile as a domicile of origin at birth (or the mother's, if the parents are separated) and never loses that domicile of origin, though it can be replaced by a domicile of choice when he/she decides to live in a place permanently (and is physically present there).
There are two main types of jurisdiction competition in divorce proceedings: the first is between two EU Member States, and it is a race. The first person to file (provided they then take the steps necessary to serve) wins.
The second scenario, when the other country is not an EU Member State, is about which of the two is the more appropriate jurisdiction in all the circumstances of the case in question, known as 'forum conveniens'.
1. Race within the EU – first in time
How to secure
One cannot over stress the importance of being first in time. Minutes and seconds can make a huge financial difference if they mean a divorce taking place in one jurisdiction as opposed to another.
How to defend
In an EU case this is virtually impossible. Attempts can be made to show that the applicant had not met one of the criteria needed to file for divorce but the recent cases of Thum v Thum  EWCA Civ 624 and MG v MG  EWHC 2035 (Fam) show that delay of service of a petition is unlikely to be sufficient for the English Court to decline dealing with the matter.
2. Non EU member state – forum conveniens
How to secure
If the competition is between England and a non-member state, the English court looks at the overall circumstances and decides which is the more appropriate jurisdiction. Although filing first can still help (especially if that is relevant in the foreign court), it is just one factor the court will consider.
How to defend
The respondent can apply for a stay and the court has discretion (under Schedule 1 of the Domicile and Matrimonial Proceedings Act 1973) to grant one if it considers that the foreign court is the more appropriate forum and if the applicant in the English proceedings can show that justice requires the English court deals with it. This is a test of fairness having regard to all the factors including the origins of the parties, the history of their relationship and the implications of granting or not granting a stay.
It is possible for two jurisdictions separately each to conclude it is the more appropriate forum, as the Court of Appeal acknowledged in Peng v Chai  EWHC Civ 1312, when the Malaysian court had not gone as far as to say it was the 'more appropriate', but had decided Malaysia was 'not an inappropriate' forum.
Hemain anti-suit injunctions
The English court does not have the power to stop foreign proceedings, but it is possible to apply for an injunction (known as a Hemain injunction) in the English proceedings which orders the other party not to pursue the litigation abroad - eg by ordering the individual not to take any further steps in the foreign proceedings until the English court has determined the question of jurisdiction. However, you have to show the other party has acted unconscionably, vexatiously or oppressively in delaying the English proceedings.
English courts only ever apply English law, however, as shown in Radmacher v Granatino  UKSC 42 there can be occasions where the fact parties signed up to a foreign law document may have an impact on the outcome of their case here.
Financial relief after a foreign divorce
Even if a divorce takes place abroad, the English Court may still make financial orders providing there is a close enough connection with England and Wales (Part III of the Matrimonial and Family Proceedings Act 1984).
How will Brexit affect this? Much depends on what deal, if any, the British Government is able to reach with the EU. No deal would likely see all cases, even those with the EU, being subjected to forum conveniens arguments. If a deal is done then much will depend on its terms and the extent to which reciprocity can be achieved if a system like the one we have now is to carry on. All that can be said for now is that the future is very uncertain.