§ 702 [Personal Knowledge Requirement for Witnesses]

Before someone can testify about something in court, they need to have actually seen, heard, or otherwise directly experienced it themselves. A witness can't just repeat rumors or guess about what happened. They need firsthand knowledge of the facts they're talking about.

If the other side objects, the person calling the witness has to prove that the witness really does have this firsthand knowledge before the testimony can continue. This proof can come from different sources, including the witness simply explaining how they know what they know. For example, a witness could say they were standing right there when an event happened, or that they personally saw a document get signed.

This rule exists to keep testimony honest and reliable. It stops people from testifying about things they only heard secondhand or assumed were true. Courts want witnesses to share what they actually experienced, not their guesses or things other people told them.

There's one exception built into this rule. It mentions Section 801, which deals with expert witnesses. Experts can sometimes give opinions based on their training and experience, even without direct firsthand knowledge of specific facts in the case. This is different from regular witnesses, who must stick to what they personally observed.