Three of the four police officers accused of killing Mthokozisi Ntumba had previously wronged the law.
It was revealed that public order policing (POP) unit officers Cidrass Motseothata, 43, Madimetsa Legodi, 37, and Victor Mohammed, 51, have had run-ins with the law.
Some of their cases date back to 2008 including attempted murder and drunken driving.
The fourth police officer, Tsepiso Kekana has no criminal case pending against him.
However, they are all in custody for shootung Mthokozisi Ntumba during students protest.