The Romans distinguished very clearly between citizens, and non-citizens, being persons who were not allowed to access the institutions of Roman law. Only citizens were entitled to use the various legal institutions of the strict ius civile, the law of Rome, which was administrated by the praetor urbanus. At the outset, Roman law did not recognise the synallagmatic contract (biliateral contract) that simultaneously creates rights and obligations. Instead, the two parties each promised a single performance (stipulatio = a stipulation), in the case for instance of a contract of sale, the “seller” would promise (stipulate) simply to deliver the object to the “buyer” who would in turn promise (stipulate) to give the “seller” a sum of money. The two promises (each constituting a unilateral contract) were enforceable independently, based on the oath made, i.e. to deliver the thing or to hand over the money. These unilateral contracts were enforced by using the strict ius civile. It was only later in the development of Roman law that the synallagmatic contract came into being, the one party’s performance being made dependant upon the performance of the other.
The law of contract in Rome was not based on general principles in the sense that as long as an agreement complied with a number of legal requirements or general principles, it would be regarded as valid. Instead the Romans had a closed system of contract, in terms of which there were specific contracts for specific agreements, each with its own requirements, formalities and characteristics, which could be utilsed to create only the obligations each of the specific contracts was intended for. Should one of the parties to the contract fail to observe the strict and formal requirements, it gave rise to invalidity of the contractual act, and the act, being a nullity, attracted no liability. These specific contracts could only be concluded by male Roman citizens over the age of puberty (or those women who were sui iuris (=in their own right), i.e. not under the manus (=hand) of a male relative or husband, but that is a discussion for a different day),1 and were normally concluded in the presence of several witnesses and (at least at the very beginning and until the late Republic) had a sacral nature. (This later changed, and Roman law recognised the so called contractus innominati, the innominate contracts, which were applied to several agreements not previously recognised as specific contracts as well as agreements that had their own specific contracts.)
As time passed and Roman influence extended to include foreigners and trade required the law to provide for trade and agreements between Romans and non-Romans, as well as between non-Romans mutually who traded in Rome, and it became necessary to adapt the strict and formal requirements of the ius civile. Therefore, a second office of praetor was created in 364 BCE by one of the leges Liciniae Sextiae,2 that of praetor peregrinus, in order to also provide remedies for non citizens and for citizens entering into obligations with non citizens.
The pr. peregrinus utilised the ius gentium, that is the law of nations other than Romans, in order to provide equitable solutions to persons who had no access to the procedures and institutions of the ius civile. In this way the praetores incorporated more and more of the equitable solutions from the ius gentium, while the ius civile, stemming as it does from the ancient and often immutable law of the original Latin tribes, was often rigid and inflexible in its results. For instance, in terms of the ius civile, it was of no consequence or interest to the law whether an obligation arose between two people as a result of fraud being committed by one of the parties. Subsequent to proper execution of the strict requirements, the obligation was regarded as established, and the ius civile had only one interest: Seeing the obligation performed properly.
The fact that one party to a contract, for instance, had persuaded the other based on fraudulent representations, did not, in terms of the ius civile, affect the validity of the obligation that arose to perform in terms of the agreement. This was so for several reasons, the most important being that Romans were honourable, and initially there was no need to provide remedies for fraud between Romans. Furthermore, concluding an agreement was a highly formalistic procedure (called mancipatio) before several witnesses and the procedure was more than a little coloured with a religious aspect, consisting of vows and solemn promises and undertakings. In short: The word of a Roman was more than his bond: It was not worth his life not to keep his promises and agreements. In any event, the agreement was initially unilateral, so what one did was simply to hold the other party to his promise, as each party’s promise stood independent of the promise made by the other.
Similarly, the ius civile took no interest whether an agreement was the result of intimidation, force, or threat of force, by one party of the other. Once the correct procedures and vows had been performed, the contract was virtually sacrosanct. A Roman simply (at least in the early development of law) did not agree to something by bowing to intimidation or the threat of force. To sum up: Good faith between bargaining parties was of no interest to the law, because on the one hand it was not necessary to require good faith among citizens, it was regarded as a given, and on the other hand, as long as the procedures had been correctly followed, the agreement was valid.
Contracting with non-Romans or between non-Romans in Rome was, however, a different kettle of fish. Foreigners simply were not to be trusted in the same way as one trusted your fellow Roman. After all, foreigners were the stuff that slaves were made of, and not to be equated with the Roman character at all. The result was that because on the one hand foreigners were not allowed access to the formal institutions of Roman law, and a Roman on the other hand (believed that he) laboured under the added disadvantage that he may be defrauded by the foreigner, it became necessary to develop legal mechanisms to safeguard the interests of both (or perhaps primarily) Romans and foreigners alike.
One of the useful and most interesting equitable remedies the pr. peregrinus brought into Roman law, was a defence on the basis of fraud being committed by the other party to an obligation. This was called the exceptio doli, i.e. a defence based on fraud (=dolus). When the emperor Caracalla decreed that all inhabitants of the empire were thenceforward Roman citizens in 212 CE, the distinction between the ius civile and the ius gentium was of no further real importance, and the defence of the exceptio doli became available to all inhabitants of the empire.
The exceptio doli is a defence based on the notion of bona fides, in that agreements became to be regarded as based on good faith between the parties. Instead of entering into an agreement by binding oneself by way of oaths and almost religious ceremony, one now bound oneself based on the notion of good faith that obtained between contracting parties. Where it transpired that one of the parties had bargained in bad faith, the other party could avoid liability by raising a defence of fraud, effectively claiming that he was not bound to honour his bargain because he had been induced to enter into the agreement based on the other party’s fraud, or bad faith.
The law towards the first century BCE had developed to a point where instead of two separate stipulations, the parties could enter into an agreement of sale (emptio et venditio = to sell and to buy), which was based on the bona fides. At this time, the parties could still make use of the original strict mechanism of two seperate stipulations, but a party had no remedy if the other had acted in bad faith, e.g. knowing that the thing exchanged, bartered or sold was defective. In the case of the contract of emptio et veditio, a party could avail himself of the exceptio doli by stating that the agreement was the result of bad faith, because he had not been informed of, for example, the defect in the thing.
Finally, all contracts in the post classical era came to be regarded as based on good faith, and the strict forms of liability in terms of the ius civile fell away, and therefore the defence based specifically on the exceptio doli was not received into Roman-Dutch law, as the notion of good faith formed the basis of contract generally, obviating the necessity for the specific defence.
1 Which indicates that Roman law was an immensely complicated set of rules, much of which we cannot even today readily digest because we don’t always fully understand how the ancient culture functioned, and law is inevitably a product of culture. So, having said that, these discussions are at best generalisations regarding an extremely sophisticated system of law and equity that still forms the basis of our modern legal discourse, often not understood, which explains why so many sudents of law misunderstand the function of law, more particularly the place of equity within law.
2 Laws (=leges) proposed by (initially only patrician) senators, were named after both the consuls for the particular year (Romans referred to years by referring to the consuls for that year, e.g. “in year of the consulship of Scaevola (hem hem) and Crassus”), in this case the consuls Licinius (the senior consul) and Sextius (his junior colleague), while legislation proposed by a tribune of the people (a plebeian official who had the right to propose legislation) was named after the tribune who proposed the law, e.g. the leges Iuliae, proposed by Julius Caesar in his capacity as tribuni plebis (=tribune of the people). (Caesar (a patrician from one of the oldest patrician families, the lulii Caesares, had himself adopted into a plebeian family for the sole purpose of being elected tribune of the plebs, but again, that is another story for another day.) Lex is feminine in gender, and therefore the adjective is also feminine (Licinius becimes Licinia, and Sextius becomes Sextia, Iulius becomes Iulia).