Two families of Pike River victims are continuing their fight to take the mine's former chief executive Peter Whittall to court.
Anna Osborne's husband Milton and Sonya Rockhouse's son Ben were two of the 29 men who lost their lives when explosions blasted through the coal mine in November 2010.
In December last year, all charges against Mr Whittall arising from the disaster were dropped.
The Ministry of Business, Innovation and Employment (MBIE) cited the lack of witness availability as a key reason for abandoning the prosecution.
More than $3.4 million in insurance money, which was earmarked for his defence, was paid out to the families of the dead men.