Under Rule 701, lay witnesses may testify in the form of opinions if the opinion is:

• A. Based on the witness's perception, helpful to understanding, and not based on scientific or specialized knowledge
• B. Based on conjecture and speculation
• C. Based on the expert's specialized knowledge
• D. Based on statistical data only

Answer: (A)

Rule 701 governs lay testimony. A lay opinion is allowed only if it is grounded in the witness’s own perceptions, helps the jury understand the witness’s testimony or a fact in issue, and does not rely on scientific or specialized knowledge. That triple requirement is why this option is correct: it states the opinion must come from what the witness perceived, be helpful to understanding, and not depend on specialized expertise.

For example, a witness who saw a car accelerate past another vehicle can say the car was speeding because that is based on what they observed and it helps explain what happened. Conjecture or guesswork isn’t allowed for lay opinions—witnesses can’t speculate about motives or mental states they didn’t perceive. If an opinion rests on specialized training or expertise, that falls under expert testimony, not lay opinion. And while data or statistics can inform opinions, a purely data-only statement without the witness’s own perception and without specialized interpretation doesn’t fit the lay-perception rule.