An associate justice or judge is a member of a judicial body. This person in authority holds a lower rank than the chief justice. In the United States, an associate justice refers to members of the U.S. Supreme Court or supreme courts in certain states. It is usually the same with other countries.
Compared to the chief justice, associate justices have lesser responsibilities. They also handle different administrative tasks. For instance in the U.S., the Associate Justice holding the most junior position is responsible for answering the door during any private conference attended by the other members of the Supreme Court.
In a judicial body, the number of associate justices varies. However, most perform similar work such as discussing together the cases presented to the Supreme Court. Each is allowed to present his side after which they cast their votes to come up with a decision on the case. The vote of the chief justice and associate justice are equal in weight when it comes to making a final decision. After a decision has been reached, an associate justice is usually tasked to write the opinion of the majority while another one performs the same task for the minority.
Associate justices are selected through different ways. The screening process normally depends on the specific court they will sit on. In some local governments, an election is conducted allowing the people to vote for the associate justices they want to serve for the area where they live. In this case, the associate justice serves for a specific term and needs to re-elected once his term reaches it end.