Short answer. Yes. Rule 76, Section 9 lists this as its own ground for disallowing a will: if the testator's signature was procured by fraud or trick, and he did not intend the document to be his will when he signed it, the court must refuse to allow it. Both parts of that description have to be shown.
What the law says
If the signature of the testator was procured by fraud or trick, and he did not intend that the instrument should be his will at the time of fixing his signature thereto
Rule 76, Section 9 — Grounds for disallowing will. Read the full provision →
A ground written specifically for this situation
Section 9 does not lump fraudulent signatures in with general fraud on the testator — it gives the situation its own paragraph. The will shall be disallowed if the testator's signature was procured by fraud or trick, and he did not intend that the instrument should be his will at the time of fixing his signature. This covers the case where someone was maneuvered into signing a document — through misrepresentation, deception, or an outright trick — without understanding, or while denied the chance to understand, that it was a will at all.
One of five grounds, not the only one
Section 9 sets out five separate grounds for disallowance: a will not executed and attested as the law requires; a testator who was insane or otherwise mentally incapable when he made it; a will executed under duress or the influence of fear or threats; a will procured by undue and improper pressure on the part of a beneficiary or someone acting for a beneficiary's benefit; and the fraudulent-signature ground described above. They are distinct — fraud in obtaining the signature does not require proving insanity, duress, or pressure from a beneficiary, though more than one ground can exist in the same case.
Two things have to be shown together
The ground has two parts, and both have to be established. First, that the signature was procured by fraud or trick — some deception actually caused the testator to sign. Second, that at the moment he signed, he did not intend the instrument to be his will. A testator who was deceived about a minor detail but still knowingly signed a document meant to be his will is in a different position from one who was tricked into signing something he never understood to be a will at all — it is the second scenario this ground targets.
What disallowance means for the estate
If the court disallows the will on this ground, that particular instrument has no legal effect as a will — it cannot be probated and cannot govern how the estate is distributed. What happens next depends on whether the testator left an earlier valid will or none at all: absent another valid will, the estate is distributed under the rules on intestate succession instead of according to the disallowed document. Raising this ground is therefore a direct attack on the document's validity, not a request to modify its terms.