MBE Rules · Contracts
Past consideration
The rule
A promise made in exchange for an act already performed is not supported by consideration — the act was not bargained for. Minority/modern exception: a promise to pay for a benefit previously received is enforceable to prevent injustice (Restatement §86).
In plain English
If someone promises to pay you for something you've already done, that promise usually isn't enforceable because you didn't agree to it beforehand.
Worked example
The defendant promised to pay the buyer $500 for fixing their car last month. Since the repair was done before the promise, it's not enforceable. However, if the buyer relied on this promise to their detriment, it might be enforced to prevent unfairness.
Memory hook
Past promises, no present power. Promising payment for past acts lacks consideration unless injustice looms.
The trap
Students think: Any past benefit can enforce a promise. Wrong, because past acts aren't bargained for. The actual test is if preventing injustice requires enforcement.
How examiners test it
The MBE loves: promise to pay after a favor done. Trap: assuming it's enforceable. Look for facts that show injustice to apply the exception.
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