Contract (conflict)

In the conflict of laws, the validity of a contract with one or more foreign law elements will be decided by reference to the so-called "proper law" of the contract.

Until the middle of the 19th century, the courts applied the lex loci contractus or the law of the place where the contract was made to decide whether the given contract was valid. The apparent advantage of this approach was that the rule was easy to apply with certain and predictable outcomes. Unfortunately, it was also open to abuse, e.g. the place could be selected fraudulently to validate an otherwise invalid contract; it might lead to the application of laws with no real connection with the transaction itself, say, because the parties signed the agreement while on holiday; or it might have been difficult to decide where the contract was made, e.g. because it was negotiated and signed on a railway journey through several states.

To avoid these difficulties, some courts proposed applying the lex loci solutionis or the law of the place of performance of the contract. This produced difficulties in cases where the contract required each party to perform its obligations in a different country, or where the place of performance was dictated by later circumstances. However, as the public policies driven by the theory of freedom of contract evolved, the Doctrine of Proper Law emerged.

The proper law of the contract is the main system of law applied to decide the validity of most aspects to the contract including its formation, validity, interpretation, and performance. This does not deny the power of the parties to agree that different aspects of the contract shall be governed by different systems of law. But, in the absence of such express terms, the court will not divide the proper law unless there are unusually compelling circumstances. And note the general rule of the lex fori which applies the provisions of the proper law as it is when the contract is to be performed and not as it was when the contract was made.

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