“This explains how a person tells the court if they did or didn't do something wrong.”
This part of the law called ‘Plea’ used to be in the Crimes Act 1961. It was about what happens during a trial and sentencing. However, this section doesn’t exist anymore. The government removed it on 1 July 2013. They did this by making a change to the law called the Crimes Amendment Act (No 4) 2011. If you need to know more about pleas in trials now, you would need to look at other, newer parts of the law.