## Facts

- The testator, in his will, instructed the trustees to use income “for the purposes indicated by me to them” and to pay capital “to such person or persons indicated by me.”
- Prior to executing his will, the testator orally informed the trustees that the funds should benefit his mistress and illegitimate son.
- After the testator’s death, his widow and legitimate son challenged the validity of the trust, claiming entitlement to the funds.
- The trust was classified as a half-secret trust: the will explicitly referenced a trust but did not name the beneficiary or disclose specifics.
- Communication of the trust’s terms occurred before execution of the will.

## Issues

1. Whether a half-secret trust is valid and enforceable when its terms are communicated to trustees before the execution of the will.
2. Whether the statutory formalities of the Wills Act prohibit pre-execution oral instructions forming the basis of a half-secret trust.
3. Whether equity may intervene to prevent a trustee from benefiting where the testator’s intentions have been communicated but not fully set out in the will.

## Decision

- The House of Lords held the half-secret trust to be valid and enforceable, as communication of the trust’s terms to the trustees was made prior to the will’s execution.
- It was established that a trustee cannot claim personal benefit when oral evidence demonstrates acceptance of trust obligations before will execution.
- The decision confirmed that half-secret trusts are recognized under law, provided the requirements of intention, communication, and acquiescence are fulfilled before the will is executed.
- The judgment asserted that equity may intervene to prevent injustice, ensuring trustees do not retain property contrary to the testator’s prior instructions.

## Legal Principles

- Validity of a half-secret trust requires intention, communication, and acquiescence before the execution of the will.
- Half-secret trusts differ from full secret trusts in that all critical elements must occur before will execution, whereas full secret trusts allow communication any time prior to death.
- Section 9 of the Wills Act formalities do not preclude equity’s intervention where a trustee would otherwise gain unjustly.
- Equity prevents trustees from profiting through non-compliance when there is clear evidence of a testator’s intent and pre-execution communication.
- The decision reinforces strict adherence to statutory requirements for testamentary dispositions while recognizing the equitable obligation imposed by half-secret trusts.

## Conclusion

Blackwell v Blackwell [1929] AC 318 (HL) affirmed that half-secret trusts are valid if their terms are communicated to trustees before will execution, requiring intention, communication, and acquiescence; the decision balances statutory formalities of wills with equitable principles to prevent fraud and ensure testamentary intentions are honored.