CAPACITY TO MAKE A WILL (TESTAMENTARY CAPACITY)
The law on capacity to make a Will is established in the common law.
The legal criterion for determining requisite capacity to make a Will was established in the 1800s by the English case of Banks v Goodfellow. Testamentary capacity is defined as the:
Ability to understand the nature and effect of making a Will;
Ability to understand the extent of the property in question; and
Ability to understand the claims of persons who would normally expect to benefit under a Will of the testator.
In order to validly make a Will, a testator need not have a detailed understanding of the points listed above. The testator requires a “disposing mind and memory,” which is defined as a mind that is “able to comprehend, of its own initiative and volition, the essential elements of will making, property, objects, just claims to consideration, revocation of existing dispositions, and the like.” 
Testamentary capacity does not depend on the complexity of the Will in question. One is either capable of making a Will or not capable of making a Will. Testamentary capacity “focuses on the testator’s ability to understand the nature and effect of the act of making a will, rather than the particular provisions of the proposed will.”
There is some school of thought in cases of borderline capacity that a change in a Will or a codicil could be undertaken where the testator understands the change in question and the reasons for the change even where it could not be said that the testator has full testamentary capacity. An example of this could be an instance where a testator with borderline capacity seeks to make a limited change by making a codicil that appoints a new executor, after the executor named in the will has died. The writer takes the respectful view that these are considerations a drafting solicitor would need to carefully and cautiously approach, perhaps with the assistance of a qualified capacity assessor, given the clarity of the requirements for testamentary capacity. Either a person has capacity to make the decision in question, or not.
The question of testamentary capacity focuses on the time at which instructions are given, not necessarily when the will is executed. Though, as our case law expands on this point, we know this to be a factor. The rule in Parker v Felgate provides that even if the testator lacked testamentary capacity at the time the Will was executed, the Will is still valid if:
The testator had testamentary capacity at the time he or she gave the lawyer instructions for the will;
The will was prepared in compliance with those instructions; and
When the testator executed the will, he or she was capable of understanding that he or she was signing a will that reflected his or her own previous instructions.
The requirements for due execution are set out in the Succession Law Reform Act (the “SLRA”).
Courts have cautioned that the rule in Parker v Felgate can only be applied where the instructions for the Will (referred to in (a) above) were given to a lawyer. In other words, even if the testator provided instructions to a non-lawyer at a time when the testator had testamentary capacity, and that layperson then conveyed those instructions to a lawyer, the resulting Will could not be valid if the testator lacked testamentary capacity on the date of its execution.
The threshold capacity required to make a Will is, again, often described as higher than the capacity required to grant a power of attorney, for property or for personal care. In fact, it simply involves different criteria applied to a certain decision. The thresholds are different.
Still, a testator need not be capable of managing property in order to have testamentary capacity. A finding that a person is incapable of managing his/her own affairs does not automatically lead to a finding that that person lacks testamentary capacity. The question of whether the testator understood his/her assets and the impact of the Will may be distinct from the question of whether the testator actually managed or had the capacity to manage his or her own property.
A solicitor drafting a Will is obliged to assess the client’s testamentary capacity prior to preparing the Will. The drafting lawyer must ask probing questions to be satisfied not only that the testator can communicate clearly, and answer questions in a rational manner, but also that the testator has the ability to understand the nature and effect of the will, the extent of his or he property and all potential claims that could be expected with respect to the estate.
In the case of Laszlo v Lawton the Supreme Court of British Columbia examined the effect of delusions on testamentary capacity. In this case, the deceased believed that she could communicate telepathically with objects by touching them; that characters on television were communicating with her; and that unidentified individuals had stolen significant amounts of money from her, among other irrational beliefs. However, these delusions were not obviously connected to her decision to disinherit her husband’s family who, on the evidence, were her previously-named beneficiaries and deserving of her generosity.
There was evidence that the deceased was still possessed of her cognitive faculties – that is, her ability to reason and remember – at the time she made her Will, in spite of the delusions (although it should be noted that there was also some evidence that she was confused and forgetful at times).
The court was left with an apparent dilemma. On the one hand, the deceased suffered from inexplicable and irrational beliefs that had only emerged in recent years; and the Will was a significant departure from the previous Will, cut out family members who would be expected to benefit, and made irrational bequests to two charities that the deceased and her husband had no affiliation with. On the other hand, there was some evidence that the deceased did not suffer from significant cognitive defects when she made her Will, and there is an apparent rule of law that non-vitiating delusions alone do not invalidate a Will.
The court reconciled these opposing factors by accepting the evidence of an expert who explained that the onset of a delusional disorder “often heralds an unrecognized and, therefore, untreated somatic illness, impacting brain function or degeneration of the brain itself.” Justice Ballance explained as follows:
It follows that the existence of delusions, while not themselves sufficient to defeat testamentary capacity, ought not to be excluded from consideration under the rubric of suspicious circumstances or the ultimate assessment of whether a testator possessed testamentary capacity at the material time. Non-vitiating delusions may reflect the ravages upon the testator’s mental functioning at large exacted by dementia or other brain disease, which cannot reasonably be ignored in the overall assessment of testamentary capacity.
In my view, consideration of non-vitiating delusions in this broader sense where the evidence suggests that all or some of the testator’s delusions accompany a progressive degenerative brain disease like Alzheimer’s does not run afoul of the rule in Banks or its lineage.
Ultimately, the court found that the testator lacked capacity, but not because she suffered from delusions. The court was not convinced on the evidence that the deceased understood the nature and quantum of her estate.
It remains to be seen whether the weight of scientific authority continues to support this opinion and whether other courts adopt this method of examining delusions as a feature of mental function at large, but notably it does seem to fit tidily into the legal analysis under Banks v Goodfellow.
Two other discussions in this case are worth noting. The court made some interesting observations about the use of MMSE results on the law of capacity. The deceased had twice been given a Mini-Mental State Examination (MMSE) around the time she made her will. She scored very well both times; i.e. the test showed no or minimal cognitive impairment. The court gave little weight to the test results, saying that the ubiquitous MMSE is a blunt tool, which has a limited ability to detect frontal lobe dysfunction or deficits in executive functioning, which are common in Alzheimer’s disease. Without more evidence of its reliability, it is impossible to determine the relative importance of its role in determining testamentary capacity.
The court also made interesting observations on the fluidity of capacity. As a generality, in the older adult, capacity will often emerge and worsen over time. However, capacity in any given case is not static. It can fluctuate slightly or wildly. There may be periods of incapacity interspersed with periods of lucidity. Appearances can be deceiving, since a person who seems rational may not have capacity and a person who seems compromised may be capable. A diagnosis of dementia is not equivalent to a finding of testamentary incapacity; testamentary capacity is a legal concept rather than a medical one and both medical and lay evidence feature importantly.
CAPACITY TO REVOKE A WILL
A testator who seeks to revoke a Will requires testamentary capacity, as outlined above.
This is clear in the case where a testator revokes a Will by executing a later Will or document.
As for revocation by physical destruction, however, for that decision to be a capable decision, the testator must be able to understand the nature and effect of the destruction and revocation at the time the Will is destroyed, and must have testamentary capacity at the time of the destruction. If the testator lacks that ability at the time of the destruction of the Will, then the Will is not deemed properly revoked. It is extremely important, as a result, to know when precisely a Will was destroyed, and if at that time the person was capable of revoking the Will.
As revocation requires testamentary capacity, in cases where a testator makes a Will and then subsequently and permanently loses testamentary capacity, that testator cannot revoke that Will. The only exception to this is if the testator marries (and has capacity to marry) at which time the Will is effectively revoked. 
CAPACITY TO MAKE A CODICIL
Subsection 1(1) of the SLRA defines “Will” as including:
(a) A testament,
(b) A codicil,
(c) An appointment by will or by writing in the nature of a will in exercise of a power, and
(d) Any other testamentary disposition. (“testament”)
Since a codicil is included in the definition of a “Will,” the criteria for determining capacity to make a Will, that is, testamentary capacity, applies equally to a codicil. (Please note the discussion above about capacity to execute limited codicils or Wills in cases where an individual may lack capacity to execute.)
CAPACITY TO MAKE A TESTAMENTARY DESIGNATION
Subsection 51(1) of the SLRA provides that “A participant may designate a person to receive a benefit payable under a plan on the participant’s death, (a) by an instrument signed by him/her or signed on his/her behalf by another person in his/her presence and by his/her direction; or (b) by will, and may revoke the designation by either of those methods.”
Likewise, a person may revoke the designation by either a signed instrument or a Will. Since a testamentary designation is by definition in a Will, or similar document, to make such a designation a person requires testamentary capacity.
 (1870) LR 5 QB 549.
 Leger et al. v Poirier,  SCR 152 at 153.
 Robertson, G., Mental Disability and the Law in Canada, 2nd ed. (Toronto: Carswell, 1994) at 214.
 Banton v Banton (1998), 164 DLR (4th) 176; Eady v Waring (1974), 2 OR (2d) 627 (CA) at page 639: “While the ultimate probative fact which a Probate Court is seeking is whether or not the testator has testamentary capacity at the time of the execution of his will, the evidence from which the Court’s conclusion is to be drawn will in most cases be largely circumstantial. It is quite proper to consider the background of the testator, the nature of his assets, his relatives and other having claims upon his bounty, and his relationship to them, and his capacity at times subsequent to the execution of the will, to the extent that it throws light upon his capacity at the time of the making of the will. Proven incapacity at a later date obviously does not establish incapacity at the time of execution of the disputed will, but neither is that fact irrelevant. Its weight depends upon how long after the crucial time the incapacity is shown to exist, and its relationship to matters that have gone before or arose at or near the time of the execution of the will itself.” [emphasis added].
 (1883), 8 PD 171.
 Succession Law Reform Act, RSO 1990, c S. 26, as amend., s. 4
 Re Fergusson’s Will; Fergusson v Fergusson (1981), 43 NSR (2d) 89 (CA); Re Griffin’s Estate (1978), 21 Nfld. & PEIR 39 (PEI CA), leave to appeal to SCC refused 24 Nfld. & PEIR 90n (SCC)
 Penny v Bolen, 2008 CanLII 48145 (Ont. SC) at para. 19: “There are different tests for the capacity to make a Power of Attorney for personal care and for property. A person may be incapable of managing property but capable of making a Power of Attorney for Property. With respect to Powers of Attorney for Personal Care the capacity threshold is much lower than for Power of Attorney for Property which is lower than the capacity required to execute a will.”
 Hamilton v Sutherland,  5 WWR 151 (BC CA).
 Murphy v Lamphier,  OJ No. 32 (CA); Hall v Bennett Estate, 2003 CanLII 7157 (Ont CA) at para. 58
 2013 BCSC 305.
 Ibid at paras 227 and 229.
 Ibid at para 199.
 This principle is outlined in the English case of Re Sabatini (1969), 114 Sol. J 35 (Prob. D.), as well as in Canadian case law in Re Beattie Estate,  3 WWR 727 (Alta. Dist. Ct.) at 729-730, and Re. Drath (1982), 38 AR 23 (QB) at 537. For more detailed discussion on revocation and destruction of wills, please see Mental Disability and the Law in Canada, supra note 78 at 224 to 225.
 Please see the section on “CAPACITY TO MARRY”.
 Re Beattie Estate, supra note 89.
This paper is intended for the purposes of providing information only and is to be used only for the purposes of guidance. This paper is not intended to be relied upon as the giving of legal advice and does not purport to be exhaustive.