Caution: Mutual Wills and Mirror-Image Wills are not the same thing!

About Jane CollisJane Collis

Jane Collis is a member of the property and private client practice group, specializing in estate planning, wills, international and domestic trusts and probate.

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I am sometimes instructed by a married couple that they want to create “mutual wills”. Generally I shudder at the thought and suggest that really what they might be after are “mirror-image” or reciprocal wills and then I proceed to explain the difference. I have only had one set of clients execute mutual wills after the proffered explanation, so I am led to the conclusion that there is widespread misunderstanding of the term. While there may be occasions for using a mutual will, in my professional opinion, they will be few and far between.

So what is the difference? In both cases of mutual wills and mirror-image wills, there will be two testators (T1 and T2) executing two wills that mirror each other in their terms. The difference is that a mutual will either expressly or impliedly creates a contract between T1 and T2 that the wills shall become irrevocable after the death of the survivor of them. During their lifetime together, T1 and T2 are free to agree to amendments to, or complete revocation of, the wills. On the occasion of the death of the first testator to die, however, the terms of the will crystallise and cannot be altered or revoked.

It is easy to see the implications of this, particularly if there is a long lapse of time between the death of T1 and T2. If over those intervening years a residuary beneficiary has died or has fallen out of favour with the surviving testator, that testator can do nothing to remedy the situation. Of course, technically, the last surviving testator could legally execute a new will, which would legally revoke the mutual will, but there would be nothing material to be gained in doing so. Equity would impose a constructive trust over the estate of the second testator to die, so the substantive benefit of his or her estate would pass according to the terms of the mutual will, and not the later will (although the later will might nevertheless be found effective to change the executors). Similarly, though marriage will revoke an existing will this is not the case with a mutual will, which will survive a testator’s remarriage, again on constructive trust principles.

In circumstances of later attempted revocation of a mutual will, or revocation by remarriage, one of the difficulties arising will be a determination of the extent of the assets covered by the “contract”. Which specific assets were bound by the contract? Was it intended to cover assets up to date of death, or only assets that were identifiable at the time the mutual wills were executed?

This obviously begs the question, why would anyone want to be so constrained? Sometimes in cases of second marriage where both testators have children from a previous marriage, there may be a genuine concern to ensure that things are kept equal and that the combined wealth of T1 and T2 doesn’t benefit only the survivor’s offspring. Likewise if T1 and T2 have no children of their own, they may wish to ensure their respective families benefit equally from their common wealth. This is a legitimate concern, but is best dealt with through the use of a trust or life insurance.

Where a mutual will is genuinely desired, then ideally there will be a separate written contract evidencing the scope, and any specific limitations, of the agreement. Although there is no legal requirement of writing, a written contract will avoid any doubt. If a mutual will is not desired but the intention is to have mirror-image wills, then consideration should be given to including a statement that the wills of T1 and T2 are not intended to be mutual. This eliminates the possibility that the matter will be open to interpretation on the death of the survivor of T1 and T2.