Career criminal Arthur Taylor and other inmates are asking the High Court to stop the election because prisoners are blocked from voting.
Taylor said there was no justification for a 2010 law change that prevented all prisoners from voting. He said that change was inconsistent with the Bill of Rights Act, and international agreements New Zealand had signed up to.
Taylor said there was no legitimate reason, such as security, that justified a blanket ban on prisoners voting.
Other prisoners from Auckland and Christchurch who are supporting the cause, previously argued the law affected Maori representation in Parliament, because a high proportion of inmates were Maori.
Lawyer for the other five prisoners Richard Francois told the court the high proportion of Maori prisoners meant up to 5000 voters are missing from the Maori roll. Mr Francois said that had a direct effect on the number and boundaries of the Maori electorates.