Stipulatio

Stipulatio was the basic form of contract in Roman law. It was made in the format of question and answer.

In order for a contract to be valid parties must have intellectus (understanding) and voluntas (wish, will). Lunatics and infants lack intellectus, which means they do not know what they are doing and so cannot contract.Slaves lack voluntas and therefore cannot contract. However, although slaves cannot be bound by a contract, they can contract to benefit their master, even without his permission, (because he will then be able to choose whether or not to enforce it or with his consent, may burden him, because he will provide the necessary voluntas. Wards and women can stipulate under their tutor’s authority) and this is not needed if they benefit under the stipulation.

The orthodox argument is that intention was not an essential condition of Roman contract law but an integral Byzantium interpolation. However, Ibbetson has argued that the intention of a contracting party was necessary. D.50.27.48 argues that, in the context of divorce, what is said in anger will not bind unless it is accompanied by action e.g. a wife saying she will walk out and then doing so. A madman cannot stipulate because he lacks understanding (G.106.) These texts combined suggest that some form of intention to be bound is required.

Agreement was an essential to having a valid contract under Roman law. Without it, the contract was void. The result of this was that animus was needed from both sides of the party in order to accept the burden and in order to accept the benefit of the contract. The texts cover two situations where agreement fails.

Firstly, if you stipulate for slave A and there are two slaves called A, which slave the stipulation is binding for depends on evidence extraneous to the verbal contract. For example, if a hand is placed on one slave.

Secondly, in the situation where a document has been used as evidence of a contract but the document is ambiguous (which is where agreement is most important) the texts discuss two possible responses. This ambiguity may be resolved against the stipulator (the approach taken by Celsus and Ulpian) or the mistake may make the contract void (the approach taken by Venellius and Paul and followed in Justinian’s Institutes.)

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