Contract; vitiating circumstances; unilateral mistake; effect of unconscionability.
Facts: Johnson offered in writing to sell 10 acres of land to Taylor for $15,000. Taylor must have known that the price was too good to be true but he said nothing and quickly accepted the offer. Johnson then said she had been mistaken about the terms of the offer. She said she had intended to offer the land for sale at $15,000 per acre, not $15,000 for the whole 10 acres. She was mistaken about what was contained in the written offer she sent to Taylor.
Issue: Did Johnson's mistake justify setting aside the contract?
Decision: In the circumstances the contract should be set aside.
Reason: This was a case of unilateral mistake, which on its own does not make a contract void. However, if one party enters a contract under a serious mistake in relation to a fundamental term, the contract will be made void if the other party was aware of circumstances that indicate the first party is mistaken, and deliberately sets out to ensure that the first party did not discover their error until it was too late. In such cases it is contrary to good conscience for the party who deliberately ignored the signs and acted to prevent discovery of the error to hold the mistaken party to the contract. The court found that Taylor had acted in this way.