What is the function of lay opinion under Rule 701?

• A. Based on specialized knowledge.
• B. To present conclusions about case facts.
• C. To provide opinions based on the witness’s perception that are helpful to understanding testimony and not based on specialized knowledge.
• D. To be used to decide the legal outcome.

Answer: (C)

The main idea is that lay opinions under Rule 701 come from the witness’s own perceptions and help the jury understand what happened, without stepping into expert territory. A lay opinion is admissible when it is rationally based on what the witness personally perceived and it aids in understanding the witness’s testimony or a fact in issue. This keeps testimony grounded in ordinary observation rather than requiring specialized knowledge.

So the function is to convey perceptions in a way that’s useful to the jury—for example, noting that a car looked like it was speeding, or that a person appeared anxious—without invoking scientific or technical expertise. If the testimony would require specialized knowledge to be meaningful, or asks the witness to make a technical or legal conclusion, that would fall outside lay opinion.