Which scenario would be inappropriate for a witness to testify about due to lack of personal knowledge?

Which scenario would be inappropriate for a witness to testify about due to lack of personal knowledge?

• A. A witness describes what they personally observed.
• B. A witness offers an opinion about something they did not personally perceive.
• C. A witness reports a conversation they heard.
• D. A witness testifies about a document's existence.

Answer: (B)

Testimony must be based on personal knowledge—what a witness directly perceived or experienced. A witness can describe things they personally observed or heard, and may offer opinions only if those opinions are based on that perception (lay opinions) or on specialized expertise (expert opinions). The scenario that asks for an opinion about something the witness did not personally perceive asks for conclusions drawn without a firsthand foundation. Without that direct perception or appropriate expertise, the testimony becomes speculative and not admissible as to facts, unless the witness is properly qualified as an expert and the opinion falls within the rules for expert testimony. The other scenarios fit within personal knowledge: describing direct observations, reporting something heard, and confirming a document’s existence all rest on the witness’s own perceptions or knowledge.

Testimony must be based on personal knowledge—what a witness directly perceived or experienced. A witness can describe things they personally observed or heard, and may offer opinions only if those opinions are based on that perception (lay opinions) or on specialized expertise (expert opinions). The scenario that asks for an opinion about something the witness did not personally perceive asks for conclusions drawn without a firsthand foundation. Without that direct perception or appropriate expertise, the testimony becomes speculative and not admissible as to facts, unless the witness is properly qualified as an expert and the opinion falls within the rules for expert testimony. The other scenarios fit within personal knowledge: describing direct observations, reporting something heard, and confirming a document’s existence all rest on the witness’s own perceptions or knowledge.