Victoria Police is being accused of defying magistrates' rulings and misusing the state's new night court system in an effort to keep a man behind bars.
The concerns come after a Melbourne man was unlawfully imprisoned following a ruling by a new night court magistrate.
Kyle Stewart was unlawfully held by police for a week on an unlicensed driving charge.
After an initial magistrate's decision that Stewart should be released, police held him for another nine hours, then took him before the new Night Magistrates Court, where a different magistrate remanded him in custody.
A subsequent hearing extended Stewart's time in the cells.
Stewart was only released from custody after a Supreme Court judge ruled that police had defied a magistrate's order.
As a result, Stewart had been held in custody, illegally, for a further seven days.
The new night court was set up in the wake of the Bourke Street massacre.
Stewart's barrister, Louis Richter, told the Supreme Court that police had been 'forum shopping' in an effort to keep Stewart locked up.
Richter compared the situation to 'North Korea or Iran'.
Victoria Police is now considering its legal options.