A witness question should begin with what the person personally observed, the opinion being offered, and the evidence rule that may apply.

Personal knowledge and lay opinion

North Carolina Rule 602 requires sufficient evidence supporting a witness’s personal knowledge. Rule 701 limits a nonexpert’s opinion or inference to one rationally based on perception and helpful to understanding testimony or deciding a fact in issue.

Expert testimony is a separate inquiry

Rule 702 addresses the type of testimony described in that rule. It identifies qualification, sufficient facts or data, reliable principles and methods, and reliable application to the facts as part of the inquiry. A court’s ruling depends on the actual witness, proposed testimony, and record.

Example: separate observation from specialized analysis

Suppose a person standing at an intersection says the signal changed to red before a vehicle entered. The foundation for that account includes where the person stood, what blocked or supported the view, what the person was watching, and how the timing was observed. The witness can describe personal observations and a qualifying lay inference without becoming an accident-reconstruction expert.

If a proposed expert instead calculates vehicle speed from measurements, video, event data, or another technical source, identify the witness’s qualifications, the data used, the method, assumptions, and how the method was applied. The example does not establish that either opinion is admissible; the court evaluates the actual foundation and proposed testimony under the applicable rules.

Preserve the foundation

  • What the witness saw, heard, did, reviewed, or measured
  • The timing, location, documents, photographs, recordings, and other sources of knowledge
  • The person’s training, experience, methodology, and materials reviewed when an expert opinion is proposed
  • Notices, reports, discovery responses, and court orders affecting disclosure

Sources