Families of the men killed in the Pike River mine blast say a $3.4 million payment does not equal justice.
A judicial review into the decision to drop charges against mine boss Peter Whittall was launched in the High Court at Wellington today.
Mr Whittall had faced 12 charges related to failing to ensure the safety of workers in the mine, but these were dropped in December 2013.
That same day, Mr Whittall and the Pike River directors offered a voluntary reparation payment of $110,000 to the families of each of the men killed in the blast, as well as the two survivors.
Sonya Rockhouse, who lost her son Ben in the explosion, and Anna Osborne, who lost her husband Milton, have taken the legal action.