What must exist for a challenge for cause to be valid?

A challenge for cause is a request made during jury selection to remove a juror from the panel due to a perceived bias or prejudice that could affect their ability to deliver an impartial verdict. For such a challenge to be valid, it is essential to demonstrate that a juror has a specific bias or prejudice. This requirement ensures that there is a legitimate concern regarding the juror's impartiality and that the legal process is upheld by having a fair jury.

The need to identify a specific bias or prejudice is crucial because it provides the basis for questioning a prospective juror's ability to be fair and impartial. This ensures that the jury is composed of individuals who can assess the case solely on the evidence presented and the law, without being influenced by personal beliefs or external factors.