As readers will no doubt be aware, the courts of England and Wales operate within a system of precedent – that is, the law is not tabulated, as in some jurisdictions, by way of a unified Civil Code, but is derived from a mixture of sources, encompassing statute, regulation, and previous decisions of courts of an equal or higher status within the court hierarchy. Now that the UK has Brexited, the decisions of the Court of Justice of the European Union are no longer binding within this hierarchy, but are of persuasive authority only. As both the UK and the EU27 prepare to amend their respective versions of the Package Travel Directive (Directive 2015/2302), with the UK’s proposal to be found here: The Package Travel and Linked Travel Arrangements (Amendment) Regulations 2026, it may be a timely moment to consider one of the less examined areas in which Member States, and the UK, currently diverge, and in respect of which there are no plans to achieve harmonisation.

Although Member States strive to achieve harmonisation, they also recognise that it is the prerogative of each individual legal system in each state to devise its own procedural rules; the EU may legislate as to substantive law, but the procedural rules to be applied by any particular court must be mandated by the governing body of that court. One very important, but under-examined, aspect of this differentiation is the concept that rules as to burden of proof form a part of the substantive law of each individual legal system (cf for example Article 22 of Regulation (EC) No.864/2007 (Rome II) as to tort law), and yet (like rules as to limitation periods) tend not to be subjected to harmonisation. This can give rise to results which we as international lawyers may find curious. Some of the Member States of the EU27 direct that the burden of proof should rest on a claimant; others state that it should fall on a defendant; others still that the burden of proof may shift depending on the particular circumstances of the case. As a consequence, a claim brought in one Member State might succeed, whereas it would fail in another because the claimant had failed to prove his or her case. This is not a glitch but a feature of EU law; it is not intended that a claim would have the same outcome in each Member State, and sometimes outcome will be determined by which of the parties bears the burden of proof.

If all of the facts are known, which party bears the burden of proof should not affect the outcome of the case. It will not matter whether it is for the claimant to prove fault, for example, or for the defendant to disprove it; the court will be able to make a determination as to whether there has been fault or not, based on the facts as they have been found. But where there is uncertainty as to a salient fact, the burden of proof may well determine outcome. Where, for example, a claimant claims damages for illness caused by food poisoning, it may be impossible to show what (s)he has eaten that has caused the illness. In such a situation, if (s)he bears the burden of proof, it will not be possible to satisfy the court that the defendant supplied the food and therefore that the claim should succeed; but if the defendant bears the burden of proof, it will not be possible to show that it was not the source of the illness. Similarly, where there is a lack of documentation as to – for example – inspection regimes, this may be a determinative feature of a case where a defendant bears the burden of proof.

The law of England and Wales has developed an interesting method of dealing with this conundrum. It is for the party pleading a fact to prove it; thus a claimant must prove that his or her cause of action is made out, whereas a defendant must prove any defence it raises. In the context of a claim involving a trip and fall in a hotel, for example, it is for the claimant to prove a breach of the applicable standard local to the hotel, but if the defendant asserts that the accident was due to carelessness on the part of the claimant, it is for the defendant to show that the claimant was indeed negligent and that this caused or contributed to the accident. This legal rule is known to every English law student as ei incumbit probation qui dicit, non qui negat (‘he who asserts must prove’).

Over time, the courts identified that this legal rule was capable of causing injustice in particular circumstances. Where for example a claimant had to prove a breach of an inspection regime, and a defendant asserted that the regime was adequate and properly implemented, but failed to disclose any documents in support of this assertion, the claimant might well fail to prove his or her case. In such a circumstance, the courts developed an evidential rule that where information resides solely within the custody of a party, it is for that party to satisfy an evidential (not a legal) burden to produce the evidence capable of proving the facts on which either party might rely. Conceptually the legal burden of proof remains with the party seeking to prove the fact, but the evidential burden shifts to the party with access to the means of doing so. In the example of the fall at the hotel, then, where the claimant claims to have fallen as a result of a spillage, (s)he must prove the presence of the spillage, but the defendant must show when the spillage is likely to have occurred, since the defendant is better placed to identify when this occurred. And, it might be added, if the defendant cannot say when the spillage is likely to have happened, it is unlikely to have been operating an adequate cleaning system at the time of the accident.

In the context of claims arising from package holidays, under the law of England and Wales it is for the claimant to prove a breach of standards local to the supplier in question. Where the claimant has fallen at a Spanish hotel, then, (s)he must show the Spanish standard relevant to the claim, whether regulatory standards as to the structure of the premises or local custom and practice as to the systems in place there. It might be thought that as the party with access to the accommodation supplier and with greater commercial leverage over it the defendant should bear the burden of proving what is required by the local standard, since this is more readily ascertainable by the defendant than by the claimant; and after all a responsible tour operator should surely be concerned to ensure that its suppliers comply with the regulations and practices applicable to them. This argument has never been properly ventilated in the higher courts of England and Wales, and accordingly, the precedents we have tend to indicate that the legal and evidential burden of proving local standards rests firmly upon the claimant at all times. However, some of the lower courts can be persuaded that because the matter has not yet been determined explicitly by the higher courts the evidential burden does shift onto the defendant to show the applicable local standard, in the interests of fairness and in accordance with the Directive’s underlying purpose of safeguarding consumer rights.

As indicated, it does not appear that either the UK or the EU27 have any intention of taking steps to harmonise the incidence of the burden of proof in these cases, and the tension between consumer protection and Member States’ individual autonomy therefore remains and is likely to continue for the foreseeable future. It is hoped that this article will shine some light on a neglected field and – perhaps – stimulate discussion of whether increased harmonisation might be considered to be desirable.

 

Sarah Prager KC, barrister, England and Wales

Deka Chambers

5/3/26

Burden of proof; package travel; England and Wales; procedural law; substantive law; Rome II Regulation; consumer protection; evidential burden; local standards; EU harmonisation; Member State autonomy; trip and fall; food poisoning.