The commission is holding day-to-day proceedings.
On May 2, Sarabjit Singh succumbed to injuries he sustained during a brutal attack by several other prisoners of Kot Lakhpat Jail.
The commission has also issued notices to Sarabjit's relatives through the Foreign Ministry to record their statements and to produce evidence they have regarding the incident.
So far, Sarabjit's family has not shown interest in getting the statements recorded, officials said.
The commission is yet to quiz the two prisoners accused of involvement in the brutal murder.
The Lahore high court has said the commission will compile its report "at the earliest".
The Indian death row convict was convicted of alleged involvement in a string of bomb attacks in Punjab province that killed 14 people in 1990.
Singh's mercy petitions were rejected by the courts and former President Pervez Musharraf.
Sarabjit's family says he is the victim of mistaken identity and had inadvertently strayed across the border in an inebriated state.