In 1930, a father bought a house for his son and daughter-in-law (Wood) to live in, telling her that the down-payment was a gift, but they were expected to pay the mortgage and that "the house will be your property when the mortgage is paid". He also said that when he retired he would put the house in their names. Wood paid mortgage instalments regularly, but when they found both the rates (property taxes) and the mortgage too burdensome, the father agreed to pay the rates as well. The father died leaving his estate to his wife (Errington). After the father's death, Wood split from Errington's son. Errington sued for possession of the house.
- Can a unilateral contract be revoked after the death of the offeror?
Denning, for a unanimous court, held there was no express promise by the son and daughter-in-law to pay the instalments, and the court cannot imply those terms. He characterizes the father's promise as a unilateral contract; the performative act paying for the mortgage, and thus it would only be revocable if the couple did not make the payments. Once performance has started the offeror cannot revoke the offer. The father's implied intention was to keep house in their possession if they paid the mortgage. The couple were on a licence, short of a tenancy but a contractual, or at least equitable right to remain, which would grow into good equitable title as soon as the mortgage was paid.
- An offeror can only revoke a unilateral contract if the offeree did not live up to their side of the contract.