The commission will hear oral arguments from the various legal representatives.
The commissioners will then submit their final report to the Presidency by the end of March 2015.
President Jacob Zuma appointed retired judge Ian Farlam to chair the commission probing the events that occurred from August 11 to 16, 2012 at Lonmin mine in Marikana, near Rustenburg. Forty-four people were killed during unrest at Lonmin's platinum mine in Marikana in August 2012.
Thirty-four people, mostly striking mineworkers, were shot dead in a clash with the police on August 16.
More than 70 people were wounded and more than 200 were arrested. The police were apparently trying to disarm and disperse them.
In the preceding week, 10 people, including two policemen and two Lonmin security guards, were killed.