How did the trial of Peter Zenger in 1733 demonstrate the need for an impartial court system?

The trial of Peter Zenger showed that the jury needs to be more diverse. The jury on his first trial were all in general his enemies(the king's council). That's not fair since they would be on the king's side and the judge makes decisions with the help of the jury and the evidence they present. This would mean an unanimous belief that he should be in jail. His second trial were full of Zenger's peers. Which may not be fair but was a victory for Zenger(with the help of famous lawyer Hamilton)