- For a will to be valid, it is not enough that the testator signed it.
- - The testator had limited English proficiency, low literacy, or a significant hearing or vision impairment, and there is no clear record the will's contents were properly explained.
Most people have heard of challenging a will because the testator lacked "capacity," or because someone pressured them into it. Fewer know about a third, separate ground: lack of knowledge and approval. It asks a narrower question — did the testator actually know and approve what was in the document they signed?
This ground often comes up in situations that look, on the surface, like a properly signed will, but where something about how the document came together raises doubt about whether the testator truly understood its contents.
Knowing this ground exists — and how it differs from capacity and undue influence — matters if you're evaluating whether a will genuinely reflects what someone wanted.
What "Knowledge and Approval" Actually Means
For a will to be valid, it is not enough that the testator signed it. The testator must have known what was in the document and approved of its contents at the time of signing. This is treated as a distinct legal requirement, separate from testamentary capacity.
A person can, in principle, have the mental capacity to make a will and still not have known and approved a particular provision — for example, if a clause was included in a draft they never reviewed closely, or if the version they signed differed from what they were told it said.
How This Differs From Capacity and Undue Influence
| Ground | What it asks | Typical evidence |
|---|---|---|
| Testamentary capacity | Could the testator understand the nature of making a will, the extent of their property, and who might reasonably expect to benefit? | Medical records, the drafting lawyer's capacity notes, contemporaneous observations |
| Knowledge and approval | Did the testator actually know and approve the specific contents they signed? | How the will was prepared, who gave instructions, whether it was read to or by the testator, literacy or language barriers |
| Undue influence | Did someone else's influence overpower the testator's own free will? | Isolation from family, control over the testator's affairs, involvement in preparing the will |
These grounds can overlap in a single case, but they are legally distinct — a challenge should identify which one (or ones) actually fit the facts.
Situations That Often Raise This Issue
- The testator had limited English proficiency, low literacy, or a significant hearing or vision impairment, and there is no clear record the will's contents were properly explained.
- A major beneficiary was closely involved in giving instructions to the lawyer or otherwise arranging the will.
- The final signed will differs meaningfully from earlier drafts, or from what the testator is known to have told others they wanted.
- The will was signed quickly, in circumstances that did not allow for a normal explanation of its terms.
None of these facts alone proves a lack of knowledge and approval — they are simply the kinds of circumstances that can justify a closer look.
What a Court Looks At
- How the will was drafted, and by whom.
- Whether the testator gave instructions directly, or through an intermediary.
- Whether the will was read over to (or by) the testator before signing.
- Whether the witnesses' evidence supports that the testator appeared to understand what they were signing.
- Whether the document's terms are consistent with what the testator is otherwise known to have wanted.
If You're an Executor Facing This Challenge
- [ ] Locate the drafting lawyer's file, including instruction notes and any capacity or knowledge-and-approval notes taken at signing.
- [ ] Identify the two witnesses and preserve their contact information and recollection while memories are fresh.
- [ ] Gather earlier wills or drafts that show — or contradict — a consistent estate plan.
- [ ] Get legal advice before responding informally to a challenge, since early statements can affect the case later.
Frequently asked questions
Is lack of knowledge and approval the same as undue influence?
No. Undue influence is about whether someone else's pressure overpowered the testator's free will. Lack of knowledge and approval is about whether the testator understood and approved the actual contents of the document, regardless of whether anyone pressured them.
Can a language barrier alone invalidate a will?
Not automatically. The real question is whether the will's contents were properly explained to the testator in a way they could understand, and whether they approved those contents. A language barrier is a fact that can support a challenge, not an automatic ground on its own.
Does the lawyer who drafted the will get involved in this kind of dispute?
Often, yes. The drafting lawyer's file and their recollection of taking instructions are usually central evidence in a knowledge-and-approval dispute, and the lawyer may be asked to give evidence about how the will came together.
How long do I have to raise this kind of challenge?
Timing depends heavily on the specific facts and stage of the estate. Ontario's general basic limitation period for many civil claims is two years from discovery, but estate litigation timing can be more fact-specific — speak with a lawyer promptly rather than assume a deadline.
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