Auckland's Manukau District Court will run two sentencing sessions a day to prevent a backlog in cases as the complex undergoes renovations.
The sentencing courts at Manukau will be run in two shifts, meaning twice as many cases can be dealt with in a week.
The first session starts at 8.30am and will finish at 1.30pm with the second running from 2pm to 7pm.
The double sessions mean up to 30 defendants will be sentenced in a day when it is rolled out in April. The current system deals with only 15.
The changes came about after chief District Court Judge Jan Doogue approached her colleagues to put together a working group of lawyers, police and judges to look at double sentencing sessions.
Manukau District Court Judge Jane Lovell-Smith said renovations at Manukau District Court meant some court rooms would be shut down at different times and something had to be done to relieve waiting times.
She said Manukau dealt with "huge volumes" of cases and something had to be done.
A spokesman from the Justice Ministry could not say what the current waiting time was.
Judge Lovell-Smith said that under the new system, sentencings would be allocated a time slot so victims and defendants would have less disruption to their day.
"For victims of crime, previously, if they wanted to come along, they had to turn up to court like everyone else and wait with no certainty that their case was going to be heard."
The working group would continue to meet over the next six months and a system would then be reviewed by the ministry.
Criminal Bar Association representative John Anderson said his group opposed the "night court'' because it would lead to lawyers and judges working unsociable hours.
He said the idea has been borne out of money saving.
"It is like saying 'let's have surgeons working around the clock'."
Auckland District Law Society court house committee convenor Iain Hutcheson said his organisation raised a number of concerns, including one from female lawyers about walking to their cars late at night.
That was dealt with by an undertaking from Ministry of Justice security staff to accompany lawyers to their cars.
He said he would like to see a review of the model if it was to be rolled out around the country.
Currently, the court building at Manukau is flanked on one side by a temporary construction fence where a $40.6 million court expansion has begun.
Work on the site has ground to a halt after Mainzeal Property and Construction announced its receivership on Waitangi Day.
A spokesman from the Ministry of Justice said Mainzeal's problems would likely extend the time for completion - originally put at November next year but would not affect the double sentencing sessions.
The redevelopment will include a new four-story extension as well as a complete refurbishment of the existing court building. It will also include four new jury trial courtrooms.