Mr Muiruri, who hails from Njora village in Kigumo Constituency, said his son had been missing for a week before his death.
The family now wants the Independent Police Oversight Authority (Ipoa) to take up the matter and investigate the case.
The man Murang’a police say hanged himself inside the operations room of Kenol Police Station on August 5 has been identified as 35-year-old Stephen Mwangi.
On Tuesday, Mwangi’s father, John Muiruri dismissed the police account after identifying the body at the Murang’a Level Five Hospital mortuary.
