§ 1451 Unenforceable Alternative Obligations

Civil Code·California

AI SummaryVerified

If a contract offers multiple ways to fulfill a duty, but one way is illegal or impossible, the law treats the remaining way as the only duty.

Key Takeaways

•If one option is illegal or impossible, the law ignores it.
•The other option becomes your full duty.
•You must perform the remaining valid option as if the illegal one never existed.

Example

You promised to deliver a package either by bike or by car, but a new law bans cars on that route.

Since using a car is now illegal, you must deliver the package by bike, and the bike option is treated as your full obligation.

AI-generated — May contain errors. Not legal advice. Always verify source.

Official Source

View on CA.gov

§ 1451 Unenforceable Alternative Obligations

If one of the alternative acts required by an obligation is such as the law will not enforce, or becomes unlawful, or impossible of performance, the obligation is to be interpreted as though the other stood alone. (Enacted 1872.)

Last verified: January 9, 2026

Key Terms

alternative acts obligation unlawful impossible of performance

References

Official text at leginfo.legislature.ca.gov
California Legislature. Civil Code. Section 1451.

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Key Takeaways

Example

Key Terms

Related Statutes

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