Why Do Liberos Wear Different Jerseys?

The libero is made to wear a different colored shirt so that the referees can spot them easily and enforce the rules of that position. “The Libero's jersey or jacket must clearly contrast in color to the color of the jersey worn by other members of the team,” state USA Volleyball's rules.

Why do liberos wear different colored jerseys?

The reason they have to wear a different colour to their team-mates is to help the referee identify them clearly and make it easier for them to enforce the rules of the libero position. Liberos have only been allowed to be the team captain since earlier this year, after the rules were changed.

Why does the libero wear a different uniform?

If the libero makes the same action behind the front zone, the ball may be freely attacked." The libero is also required to wear a different color jersey, presumably to make it easier for referees to enforce those rules. The liberos aren't subject to the same substitution rules either.