i used to be interested in mental health and brain science evidence primarily as a basis for understanding criminal legal responsibility (insofar as we are beginning to acknowlege the neurobiological bases of our actions) and in memory formation and the relationship between interrogation procedure and the validity of eyewitness testimony. i am also interested, peripherally, in the issue of vitiated consent (whether you knew the nature of what you were consenting to — say in rape cases involving someone with a low iq or with a mental disability.) estate litigation, on the other hand, was not an area of law i’d paid the slightest attention to (i mean, relatives squabbling for a more favourable share of grandpapa’s legacy — that kind of thing is so boring.) what i’d never anticipated was that in singapore, that, rather than the criminal law, would be the place where medico-legal questions about the brain and the mind would start to be fought out. looking for cases on the duties and liabilities of court-appointed deputies for the mentally-incapacitated for a class, i found instead case after case about contested wills.

of course wealthy and litigious families have always existed (the wealthier the more litigious it would seem) — but in the past i think many of these cases would have been fought on the basis of undue influence/unconscionability or resulting trust/presumption of advancement principles. now, it seems instead that more and more wills are being disputed for their essential validity based on allegations of the testator’s lack of mental capacity, and i’m turning up more cases, from 2011 onwards, where psychiatric and neurological clinical evidence, including brain scans, are being produced in court on either side of the dispute. yesterday, for instance, i came across one where the testator was a schizophrenic for 42 years, who made a will favouring one branch of the family 4 years before his death, and whose testamentary capcity was vigorously contested by other family members who would have taken under intestacy laws. in another, alzheimer’s was alleged and MRI scans were produced to show degeneration or impairment in ability (although it was not clear how that evidence was presented and interpreted, or what attempts were made to explain the medical evidence in a way that is both consistent with the ways scientists understand it and has legal meaning for legal practitioners — that again depends on our understanding of what medical evidence or brain images can and cannot tell you — for even if brain imaging evidence shows impairment or degeneration of ability one still has to show the connection between the clinical evidence and the actual functional realities and daily aspects of someone’s life, no?)

surely too, the use of such clinical evidence masks the many personal and emotional motivations behind how we make decisions on a daily basis. now, of course i accept that mental illnesses go to the root of your thought processes themselves and that they have a medical/biological basis, and i don’t want to in any way downplay the difficulties someone suffering from a mental illness experiences, but i simply do not accept that you have no legal capacity to make decisions for yourself solely because of your condition. and come to that, why should we conflate validity of testamentary disposition with rationality of action? people do what looks irrational to other people all the bloody time.

because surely that confuses the medical with the legal issue: even if you suffered from some kind of mental illness and that was the cause, say, of your (totally unfounded) belief that you were being persecuted by your family members, and let’s say on that basis you decided you were leaving all your money to the SPCA instead so that it doesn’t get into the hands of those nasty relatives � well, so what? however imaginary or irrational your motivations are, the point is, and it is a legal point, that the proof of testamentary capacity is that you a) understood the nature of the act of making a will and its consequences b) knew the extent of your property and what you were disposing of, c) knew who the beneficiaries were d) and were free from some abnormal state of mind at the material time (say you were so heavily intoxicated or under medication that prevented clear thought). that must be what is alleged and proved, not the existence of the condition itself, nor the content of the will. rationality has nothing to do with it: what i mean is, if i made a will today giving my money to the law canteen prata stall (and my well-publicised hatred of the law canteen is so well-known to the second-year class that no one would countenance this), you might certainly have cause to suspect it was a forgery, or that i had made it with a pistol to my head, and if it were forgery or duress, yes, set it aside. but if it turns out i had in fact made it, however capricious and incomprehensible the content, no one can doubt that i have the capacity to make this will, just because i wanted to. �because i want to� is in the very nature of a proprietary right � i can make dispositions of my proprietory interests to whoever i damn well please, even my deadliest enemy.

it is not just the question of why we in our definition of �normal� or �rational� should be so restrictive of the variety of human action, desires and impulses. it goes further than that: how can we ever really unpack what is behind our motivations for doing anything, conscious or unconscious, even when we seem to do so rationally? for our desires are just as slippery, our sense of normal illusory. we are so quick to assume that people cannot decide for themselves, that if what they do does not seem logical by �normal� standards they must be incapable, that our beliefs override theirs.

if you don’t like a will someone’s made, by all means, challenge the distribution on the basis of estoppel or detrimental reliance or undue influence or resulting trust or whatever. but to invalidate a will by taking away someone’s right to express their wishes, to challenge his action to mental capacity, that is a serious matter that goes to the heart of their self-determination and autonomy, and i find that nearly as outrageous.