Insane Delusion and Mistake as Grounds to Contest a Will in New York

Most will contests in New York are fought on three grounds: the will was not properly signed, the decedent lacked capacity, or someone exerted undue influence. Two further grounds come up less often and are less well understood, by clients and sometimes by lawyers. The first is insane delusion, a narrow form of incapacity in which a person who is otherwise competent holds one fixed false belief that drives the will. The second is mistake, which in New York is usually not a ground for denying probate at all, with narrow exceptions. We have pleaded and defended both in the Surrogate's Courts of New York City, Long Island and Westchester, and this page explains when they are worth raising and how they are proved.

Insane delusion: a fixed false belief that drives the will

The general test for capacity asks whether the decedent understood, in a general way, the nature and consequences of making a will, what property they owned, and who their natural heirs were. A person can pass that test and still lack capacity as to a particular will if the will is the product of an insane delusion. The doctrine recognizes that a mind can be sound on every subject but one, and that when the one subject is the family, the will can be the delusion's handiwork.

New York courts require two things, and both must be proved.

• A delusion. A fixed belief, with no basis in fact, that the decedent held against all evidence and reason and that no rational person in the decedent's position would have held. It must be a belief that persists in the face of proof to the contrary, not an opinion, a suspicion, or a conclusion drawn from thin evidence.
• Causation. The delusion must have produced the disposition. If the decedent would have made the same will without the delusion, the will stands even if the delusion is proved.

The definition rules out a great deal. A parent who believes, wrongly but on some evidence, that a child has been ungrateful, or has enough money already, or married badly, is not deluded; they are mistaken, or unfair, or mean. New York law lets a competent person make an unjust will for a bad reason. A belief with any real foundation in fact, however slight, is not a delusion. What the doctrine reaches is the belief that has no foundation at all and that the decedent kept holding after being shown that it was false.

Classic examples

• A father who became convinced, with no basis, that his son was not his biological child, and disinherited him for that reason, after DNA evidence or the plain family history showed otherwise.
• A widow who believed her daughter was poisoning her food and cut her out of the will, when medical testing and everyone around her confirmed there was no poison and no attempt.
• A decedent who believed that a sibling or nephew had stolen large sums from them, and made a will to punish the theft, when bank records showed no money had ever gone missing.

How insane delusion differs from incapacity and undue influence

Insane delusion is a species of lack of capacity, and it is almost always pleaded together with general lack of capacity and with undue influence. The three overlap in the evidence but not in the theory.

The reason to plead them together is that the same story often fits more than one. A decedent with early dementia who is told repeatedly by a caregiver that the children never visit and are waiting for the money may end up with a fixed false belief that the children have abandoned them. Is that a delusion, or undue influence, or simple incapacity? It may be all three, and the jury or the Surrogate may accept one theory and reject another. Pleading each separately keeps every route open. We explain the general capacity test on our page on testamentary capacity and the influence theory on our page on undue influence in will contests.

Proving an insane delusion

Because the doctrine turns on what was in the decedent's head, and on whether it was true, the proof comes from four sources.

• Medical records. Notes of paranoid ideation, psychosis, delirium, late-stage dementia with delusional features, or psychiatric medication are the foundation. A treating physician who recorded "patient believes daughter is stealing from her; no evidence of this" has written the objectant's opening statement.
• Psychiatric testimony. A forensic psychiatrist or geriatric neurologist, working from the records and from witness accounts, can testify to whether the belief has the character of a delusion and whether the decedent's condition produced it.
• The decedent's own statements. Letters, emails, voicemails, statements to the drafting attorney, to friends, to bank officers, and to the attesting witnesses. The drafting attorney's notes are especially important, because a decedent who tells the lawyer "I am leaving my son out because he is not really my son" has connected the belief to the disposition in their own words.
• Proof that the belief was false. Bank records showing that no money was taken. A DNA test. Medical evidence that there was no poisoning. Testimony from the people who tried to correct the belief and were rebuffed. The falsity must be objective, and the objectant must prove it.

The examinations of the attesting witnesses and drafting attorney under SCPA 1404 are where much of this is first uncovered. We ask the drafter what reason the decedent gave for the disposition.

Causation and partial invalidity

The delusion must have caused the disposition. A decedent who believed a neighbor was spying on them, and who left the estate to their children in equal shares, made a will that no delusion touched.

When the delusion affects only one gift, the court can deny probate to that gift and admit the rest of the will. The disinherited child's share then passes under the residuary clause or, if the delusion affected the residuary itself, by intestacy. Partial invalidity is available for insane delusion in the same way it is available for undue influence and fraud, and the objectant should ask for it in the alternative.

Mistake

Clients often come to us saying that the decedent made a mistake: they left out a grandchild born after the will was signed, they thought a son was wealthy when he was not, they believed a daughter had already been given her share. The instinct is that a will based on a mistake should not stand. In New York, that instinct is usually wrong.

Mistake in the inducement

A mistake in the inducement is a wrong belief about facts that motivated the decedent to make a particular gift, or to omit one. The decedent believed that a nephew was dead, or that a child had already been provided for, or that a friend had been generous to them. The general rule is that a will is not denied probate for a mistake in the inducement. The decedent knew what the document said and intended to sign it; the court will not rewrite the will to reflect what the decedent would have done if better informed.

There is a narrow exception. If the will itself recites the mistaken fact as the reason for the disposition, and shows on its face what the decedent would have done had the fact been otherwise, some courts will give effect to the stated intention. A clause saying "I leave nothing to my son John because he died in 2019" might be disregarded if John is alive. Such clauses are rare.

Mistake in the factum

A mistake in the factum is a mistake about the document itself: the decedent did not know what the paper said, signed the wrong document, or believed they were signing something other than a will. This is not really a species of mistake at all. If the decedent did not know the contents, there was no testamentary intent, and a document signed without intent to make it a will is not a will. If the decedent was led to sign the wrong document by someone else, that is fraud. Either way the will fails, but it fails under the ordinary doctrines of intent and fraud, and the objections should be drawn that way. Two spouses signing each other's mirror wills by accident is the classic example.

Reforming a will for a drafting error

A different problem is the will that says something the decedent plainly did not mean because the lawyer or typist made an error: the wrong article number is referenced, a residuary clause is missing, a beneficiary's name is wrong in one place and right in every other. New York courts have historically refused to reform a will to correct a mistake, on the ground that the court's job is to admit or reject the document the decedent signed, not to write a better one. In recent years there has been a visible trend, in construction proceedings rather than in probate itself, toward correcting obvious clerical errors where the decedent's intent is clear from the will as a whole and the surrounding circumstances. The relief is still exceptional, it is sought after the will is admitted and not as an objection to probate, and it depends on the court being satisfied that it is fixing a scrivener's slip rather than remaking the plan.

When a mistake becomes fraud

A mistake in the inducement is not a ground for objection. A mistake induced by someone's lie is. If the decedent disinherited a daughter because they believed she had stolen from them, and that belief came from a son who told them so knowing it was false, the ground is not mistake but fraud, and the will can be denied probate as to the gift the lie produced. The objectant must prove the false statement, the speaker's knowledge that it was false, and that the decedent relied on it in making the disposition. See our page on fraud in the execution of a will.

When these grounds are worth pleading

We plead insane delusion when three things line up: the decedent's stated reason for the disposition is provably false, there is medical evidence of a condition that produces delusional thinking, and the belief cannot be explained as a bad but rational judgment. When only one or two of those are present, the same facts generally belong in the capacity and undue influence objections, where they do useful work without the added burden of proving a delusion.

We rarely plead mistake as a freestanding ground, because it usually is not one. What we do is trace the mistake to its source. If it was a lie, it is fraud. If the decedent did not know what they were signing, it is lack of testamentary intent or fraud. If the will contains a clerical error, the remedy is a construction proceeding after probate, not objections.

How we can help

We evaluate these grounds by reading the medical records and the drafting attorney's file before objections are due, and by asking at the SCPA 1404 examinations what reason the decedent gave for the disposition. If you believe a will was written by a false belief, or a lie, or a document the decedent never understood, we can tell you whether the facts support an objection and on which ground. Call us at 212-233-1233 or email [email protected].