From Max-EuP 2012

by Sebastian A E Martens

1. Object and historical background

Freedom of action is an essential prerequisite of private autonomy (freedom of contract). However, quite apart from the fact that all legal systems regularly restrict this freedom by mandatory rules, they cannot make complete freedom a condition for the validity of juridical acts because we are permanently exposed to all kinds of pressure. Total protection from such pressures would abolish private autonomy. Therefore, every legal system has to distinguish between different forms of pressure, and it has to determine the legal consequences for juridical acts that have been caused by such pressures.

Today, all European legal systems draw a distinction between vis absoluta and vis compulsiva. Vis absoluta exists if the coerced person is a mere instrument in the hands of the coercer. In such a situation there is no action which can be attributed to the coerced person, and any prima facie juridical act of that person is void. Vis compulsiva on the other hand does not vitiate the will of the coerced person but only directs the person’s will according to the wishes of the coercer. Thus, juridical acts made in a state of vis compulsiva will be attributed to the coerced person in order to protect legal certainty. Only under certain circumstances are they held voidable at the option of the coerced person. Such a right of the coerced person to avoid his juridical act can be justified along two different lines: (1) The use of illegitimate pressure can be regarded as a tortious act that cannot be tolerated by the legal system and that has to be repressed by sanctions. By providing a right of avoidance the legal system makes it unattractive to use illegitimate pressure in contractual negotiations. (2) A right of avoidance can also be seen as a means to protect the coerced person’s freedom of decision. The right of avoidance has the purpose of enabling the coerced person freely to decide about his further obligations after he has been relieved from the pressures.

In concretely shaping this right of avoidance, some European legal systems have primarily focused on repressing the use of illegitimate pressures, some have concentrated on the protection of freedom of decision and some have stressed the importance of legal certainty. However, the law in force is not always a rational compromise of these conflicting interests, but in large parts can only be explained as the result of historical developments. The continental legal systems are still influenced by their Roman-law tradition (Roman law) and the Roman remedies in cases of metus. The Roman praetor granted an action for restitution if something had been transferred ‘because of fear’, and he allowed a defence against all claims that had been obtained as a result of fear. A special feature of both remedies was that it was irrelevant whether or not the opposing party had been privy to arousing the fear. Thus, an action for metus required only that the defendant had obtained the disputed object or obligation ‘because of fear’. This was in sharp contrast to the cases of fraud (dolus) where remedies were only granted against the fraudulent person himself.

In the Middle Ages, the glossators distinguished between different forms of coercion (vis). They assigned vis compulsiva, ie overbearing coercion, to metus and its respective legal remedies. Thus, the glossators changed the focus from the vice of consent resulting from fear to the delict of extortion. This explains why, today, the term ‘fear’ (Furcht) can only be found in Austrian and Swiss law while most continental legal systems refer to threats or other means of arousing fear (Drohung, bedreigning, violence, intimidación).

The delictual understanding of metus did not prevent the glossators, being inspired by a fragment of the Digest, from treating metus together with dolus (fraud) as an impairment of the consensus that was now generally deemed necessary for the validity of contracts. However, consensus was no longer used in the Roman sense of signifying the mutual agreement between the contractual parties. Rather, the concept of consensus now described the individual consent of each party (ie his Willenserklärung, as it was now termed), which corresponded to the other party’s consensus. Thus, duress along with fraud and mistake became one of the three classic vices of consent.

2. Trends of international legal development

In Roman law, threats were only relevant if they would have caused a homo constantissimus, ie a very resolute man, to act in the same way as the coerced person had actually done. Such an objective standard for a legally relevant threat can still be found in Art 1112(1) Code civil and Art 3:44(2) Burgerlijk Wetboek (BW), both of which require the threat to have been of a force to move a reasonable person. However, in interpreting these norms the special circumstances of the coerced person (age, sex, character, etc) are to be taken into consideration. Thus, these legal systems effectively also apply the subjective standard, commonly used in Europe now, according to which it suffices if a threat has caused the juridical act in question.

For a long time, English common law did not grant a right of avoidance (invalidity) in all cases of illegitimate coercion. Rather, there existed intricate case law which covered different types of situations. The common law doctrine of duress used to be very narrow and was even associated with the doctrine of non est factum, ie cases where a defendant could argue that the act in question ‘had not been done’ by him. This idea is still sometimes reflected by the language of the courts which explains that the will has been ‘vitiated’ in cases of duress. Initially, only duress to the person was recognized and as late as 1840 duress to goods was explicitly rejected. Today, duress to goods is seen to be an instance of economic duress that has since the 1970s been held to be a reason for a right of avoidance. Economic duress came to be recognized in situations where somebody had extorted a contractual amendment by illegitimately threatening a breach of contract. The courts held that the coerced party could avoid the amendment if he had no reasonable alternative but to agree to the demanded amendment. Some legal writers argue for such an objective criterion for the continental legal systems as well, where causation of the threat and its illegality are generally held to be sufficient for a right of avoidance.

In England, legal writers proposed that the common law doctrine of duress and the equitable doctrine of actual undue influence should be merged and that there should be a right of avoidance in all cases of an illegitimate threat. Thus, illegality of the threat has emerged as the most important normative criterion for determining a relevant threat. However, no clear formula has yet been found conclusively to define this concept of illegality.

Significant disparities between the European legal systems still exist as to their reactions to threats by third parties. While German and French law, for example, are true heirs of the traditional Roman law and therefore grant a right of avoidance in all cases of a threat by a third party, other legal systems give more protection to the interests of the contractual partner who is affected by the avoidance of his contractual rights. For this purpose of protection, the legal systems use a number of different instruments: some grant a right of avoidance only if the contractual partner knew or should have known about the threat by the third party, and some distinguish between threats according to their severity. Other legal systems grant a right of avoidance in all cases of a threat by a third party, but they allow the contractual partner to recover from the coerced person avoiding the contract the loss which he incurred in relying on the validity of the contract. Still other legal systems allow avoidance only as long as the contractual partner of the coerced person has not yet made any disposition in reliance on the validity of the contract. However, all legal systems require that the third party aimed at the conclusion of the contract in question by his threat. Such a link was initially only demanded in three-party constellations, but today it is deemed to be necessary even in a two-party situation where one person forces another person to contract with him.

Apart from this, only minor subjective requirements as to the coercer are now made. Because of the delictual character of the concept of threat, the coercer once had to have known about the illegality of his threat, but today it is generally held to be sufficient if he had acted intentionally or recklessly with respect to the threat (regardless of its legal qualification) and if the threat had caused the juridical act in question.

A right of avoidance is usually only discussed if the coercive force stems from some human source. Juridical acts that have been caused by other pressures will not be governed by the rules as to duress or threats, but may only be attacked under the doctrine of unconscionability (illegality of contracts). Only French law recognises violence économique in specific situations where transactions have been made in a state of (economic) emergency.

3. Duress in the harmonization projects

The multitude of common features or at least converging tendencies of the European legal systems in their treatment of duress has made it possible to formulate almost identical uniform principles in Art 3.9 UNIDROIT PICC and Art 4:108 PECL. These principles shall be examined in more detail in the following discussion. The DCFR adopted the rule of Art 4:108 PECL with only minor linguistic corrections in Art II.-7.206.

Both Art 3.9 UNIDROIT PICC and Art 4:108 PECL limit themselves to providing a right of avoidance in cases of overbearing coercion (vis compulsiva) in the form of threats by other human beings. Thus, vis absoluta and natural pressures are not covered by these provisions. There is no definition of the concept of ‘threat’ in either UNIDROIT PICC or PECL. However, a ‘threat’ is generally understood to mean the announcement of a future detriment which will be brought about by the threatening person if the threatened person does not perform the demanded act. In principle, both Art 3.9 UNIDROIT PICC and Art 4:108 PECL regard a threat with any harm as sufficient and they do not restrict themselves to special types of cases.

A ‘threat’ has to be distinguished from mere warnings about harm, the possible occurrence of which can not be attributed to the warning person who is therefore not responsible for them. The European legal systems generally only recognize a threat as relevant if the threatening person has announced a detriment that he will actively bring about. They are restrictive in acknowledging a legally relevant threat if the threatening person has only announced that he will not avert some future harm. Thus, they are hesitant to accept duties of assistance in cases of pressure. According to the wording of Art 4:108 PECL, this rule only covers a threat of an act to bring about some harm but not a threat of an omission to avert some harm.

Not every threat gives rise to a right of avoidance: it also has to be made illegitimately. The concept of illegitimacy is specified in more detail by two types of cases in Art 3.9 s 2 UNIDROIT PICC and Art 4:108 PECL. Thus, on the one hand a threat is regarded as illegitimate if the means used to cause the threatened harm are illegitimate themselves. This does not cause problems in cases of a threatened bodily injury or damage to property. But difficulties arise if the threat consists in a breach of contract in order to enforce re-negotiations. If a contract is amended in such a situation, the European legal systems do not always give a right of avoidance.

A threat is, on the other hand, also taken to be illegitimate if it is legitimate for the threatening person to inflict the threatened harm in principle, but not if he applies it as a means to bring about the demanded conclusion of a contract. This second type of case of illegitimate threats is also widely acknowledged in the European legal systems, although there are different views as to when exactly the use of a means to the end of bringing about the conclusion of a contract is to be regarded as illegitimate.

The threat needs to have caused the threatened person to enter into a contract. Such a causal link is generally held to exist if the threat was at least one of the causes for the threatened person to enter into a contract, ie if the threat was a conditio sine qua non for the conclusion of the contract (‘but for’ test). However, it is not clear how this relates to the rule of exclusion of a right of avoidance in Art 3.9 s 1 UNIDROIT PICC and Art 4:108 PECL in cases where the threatened person had a reasonable alternative to entering into the contract. Until now, this exception from the general right of avoidance has only (explicitly) been acknowledged in the English common law where it is restricted to certain types of cases (eg a threatened breach of contract) while it has gained a general status in UNIDROIT PICC and PECL. The uncertainty in determining the legal relevance of a reasonable alternative is mainly due to the fact that its systematic classification is not yet settled. Sometimes it is seen as an objective exception to the generally subjective concept of causation; sometimes the fact of a reasonable alternative is thought to somehow influence the concept of illegitimacy.

Neither Art 3.9 UNIDROIT PICC nor Art 4:108 PECL explicitly state any subjective conditions as to the threatening person. Yet, both provisions seem to follow the common European tradition that recognizes a legally relevant threat only if the threatening person acted at least with dolus eventualis, ie he knew that the threat could cause the conclusion of the contract, and he accepted this possibility. UNIDROIT PICC and PECL also do not answer the question of whether the threatening person has to have aimed at the conclusion of the contract.

The case of duress by a third party, different from the contractual partner, is governed by Art 3.11 UNIDROIT PICC and Art 4:111 PECL. These provisions treat the cases of duress and fraud by a third party alike and thus give up a distinction stemming from Roman law which is still drawn in many European legal systems. Under Art 3.11 UNIDROIT PICC and Art 4:111 PECL a right of avoidance is granted if the contractual partner can be held responsible for the acts of the third party, or if the contractual partner knew or could reasonably be expected to have known about the threat by the third party. Article 4:111(2) PECL also gives a right of avoidance if the contractual partner has not yet made any disposition relying on the validity of the contract.

The right of avoidance is exercised by a unilateral declaration. In contrast to many legal systems, neither PECL nor UNIDROIT PICC specify a fixed limitation period for the right of avoidance. Instead, they only demand that the right is exercised by the threatened person within a reasonable time after he has been freed from the pressure.

Apart from the right of avoidance of the extorted contract, Art 3.18 UNIDROIT PICC and Art 4:117 PECL also grant a claim for damages to the threatened person against his contractual partner. Damages may be claimed alternatively to, or cumulatively with, the avoidance of the contract, and they comprise all loss caused by the illegitimate threat.

4. Uniform law

Apart from the provisions of UNIDROIT PICC and PECL discussed above, no norms covering duress in the contracting process can be found in international model laws of other treaties. For example, Art 4(b) CISG excludes any question as to the validity of the contract from its scope of regulation. Thus, the legal consequences of fraud or duress in the contracting process are not covered and their regulation is left to the national legal systems. On the European level, Dir 85/577 covers only one special type of pressure in consumer contracts, ie contracts negotiated away from business premises where it is supposed that salesmen usually apply some sort of undue influence. Although this influence generally does not reach such an intensity that its application could be regarded as illegitimate, the consumer is granted a right of withdrawal from the contract within a defined cooling-off period (doorstep selling).


André Breiton, La notion de la violence en tant que vice du consentement (1925); Patrick Selim Atiyah, ‘Economic Duress and Overborne Will’ (1982) 98 LQR 197; Alan Wertheimer, Coercion (1987); Reinhard Zimmermann, The Law of Obligations, ch 21: ‘Metus and Dolus’ (1990); Tony Weir (tr), Hein Kötz, European Contract Law, vol I (1997) 209 ff; Thomas Gutmann, Freiwilligkeit als Rechtsbegriff (2001); Martin Josef Schermaier ‘§§ 116–124. Willensmängel’ in Mathias Schmoeckel, Joachim Rückert and Reinhard Zimmermann (eds), Historisch-kritischer Kommentar zum BGB, vol I (2003) nn 104 ff; Jacques du Plessis, Compulsion and Restitution (2004); Thomas Schindler, Rechtsgeschäftliche Entscheidungsfreiheit und Drohung (2005); Nelson Enonchong, Duress, Undue Influence and Unconscionable Dealing (2006); Sebastian Martens, Durch Dritte verursachte Willensmängel (2007).

Retrieved from Duress – Max-EuP 2012 on 24 January 2022.

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