Firsthand knowledge refers to something which the witness actually saw or heard, as distinguished from something he learned from some other person or source. It is also a knowledge that is gained through firsthand observation or experience, as distinguished from a belief based on what someone else has said. The federal rules of evidence requires lay witnesses to have personal knowledge of the matters they testify about. It is an affidavit that is based on personal knowledge, unless the affiant makes clear that a statement relies on “information and belief”.
The following is a caselaw defining firsthand knowledge:
Firsthand knowledge are facts within the personal knowledge of the expert.[State v. Burrell, 2006 Minn. App. Unpub. LEXIS 1117 (Minn. Ct. App. 2006)].