Rule 603 Oath or Affirmation

Every witness who takes the stand must promise to tell the truth before they can testify. This promise can be a formal oath or a simple affirmation, but either way it has to happen first.

The point of this promise is to remind the witness how important it is to be honest. The words used should be serious enough to make the witness stop and think about their duty to tell the truth. Courts have some flexibility in how they word this promise, as long as it gets the message across.

This matters because it puts the witness on notice that lying under oath is a serious matter with real consequences. It also gives the court a formal moment where the witness commits to honesty before answering any questions.