Human conscience will appear in the Purgatory
In the Purgatory, no one is allowed to talk without God’s permission.
From the beginning of death, the universe of purgatory will start, where human has no free will, he cannot tell lie, and will not be able tell anything but the truth. The angels only face his conscience not his body.
In the Purgatory man will realize that when he was living, all his actions were done actually by his conscience not by body.
It is the conscience which talks to the angels, and man will respond by his soul, his conscience, therefore he tells only the truth.
In the Purgatory man will see the consequences of his actions done during his life meaning what he is done all will be presented:
Those who live off orphans property without having any right to do so will only suck up five into their bellies (4:10)
Announce painful torment to those who heard gold silver and do not spend them for God’s sake.
Some day [these metals] will be heated up in Hellfire, so their foreheads, sides and backs may be branded with it: “this is what you have hoarded up for yourselves, so taste what you have been hoarding”! (9:34-35)
Sources :
"Recognition of Resurrection" (By Allameh Tehrani)