The short answer
What Illinois families should know.
A witness ordinarily needs personal knowledge of the facts described. Guessing about a spouse's motives or filling a memory gap with a confident answer can weaken the evidence. Illinois Evidence Rule 602 requires a foundation showing that the witness knows the matter being described. Careful limits make testimony more useful.
Explain how you know
The foundation may be simple: you attended the exchange, received the message, made the payment, or maintained the household account. Start with the event and your connection to it. Seeing a withdrawal on a statement establishes something different from watching the money being spent. A useful witness separates those observations rather than treating both as direct knowledge of the same transaction. Tell counsel before trial if your understanding came entirely from someone else's account.
Separate inference from observation
People draw everyday inferences, and some lay opinions are permitted under Evidence Rule 701. The opinion must have the required connection to the witness's perception and help explain the testimony or a fact at issue; it cannot rest on specialized knowledge reserved for expert testimony. Seeing a parent arrive late does not establish why that parent was late. Describing observable behavior is different from diagnosing a disorder or predicting a medical outcome.
Identify the limits of a recollection
An approximate memory should be described as approximate. You may remember that an event happened during a school break without recalling the precise day. Explain that distinction instead of selecting a date because it seems plausible. Confidence and precision are different: someone can be certain an exchange occurred while uncertain about its time. Before the hearing, list the facts you remember independently and the details that require a supporting record.
Use documents without claiming a memory you lack
Reviewing a bank statement or calendar can help preparation, but it does not always produce an independent recollection. If you know an amount only because it appears in a document, say so. Counsel can address how the record should be introduced and what testimony is appropriate. Do not invent the surrounding conversation to make the evidence sound more complete. An honest statement that you do not know leaves the court with a clearer record than a guess presented as an observation.
Prepare
Useful next steps
- List the events you personally saw, heard, or handled.
- Identify which details come from records rather than independent recollection.
- Tell counsel about assumptions and information supplied by other people.
Avoid
Common missteps
- Guessing to appear helpful or certain.
- Offering a specialized medical or financial conclusion as an ordinary observation.
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This article provides general information and is not legal advice. Laws, court rules, local procedures, and individual facts can change the analysis. Reading it or contacting the firm does not create an attorney-client relationship.