Evidence
Lay Witness
Definition
A lay witness testifies based on personal knowledge and perception rather than specialized expertise. Under Federal Rule of Evidence 701, a lay witness may offer opinion testimony only if it is rationally based on their perception, helpful to determining a fact in issue, and not based on scientific, technical, or specialized knowledge within the scope of Rule 702 (expert testimony). Common examples include opinions on speed, sobriety, handwriting identification, and emotional state.
Example
A witness at the scene of a car accident testifies: 'The car was going about 60 miles per hour.' This lay opinion based on personal perception is admissible under FRE 701.