A police officer attached to Starehe DCI had sought to detain lawyer Assa Nyakundi in connection with the death of his son in Muthaiga.
According to affidavits before court, PC Godfrey Munene had on Thursday requested for 14 days to conclude investigations into the death.
Senior principal magistrate Angelo Kithinji, however, declined to grant the orders and asked the investigating officer to serve the lawyer with the application.
He ordered that immediately the suspect is discharged from hospital he appear in court.
Nyakundi's son was fatally injured after being shot by his father as they returned to their Muthaiga home from church on Sunday.
Nyakundi said he was trying to holster his firearm when he accidentally fired, shooting his son.
Detectives on Tuesday said Nyakundi shot two bullets during the incident that left his son dead.
An autopsy report released on Thursday suggested Nyakundi's son was shot outside the car.
Nyakundi was arrested on Sunday and temporarily released from custody after falling ill.
He has been at Nairobi hospital.
Munene's affidavit reads, "The deceased is his biological son and family members including his household employees are potential witnesses and we are apprehensive that if the suspect is released back to his home and normal life, upon discharge from hospital, he may interfere with the witnesses who have not recorded their statements."
He further said other exhibits, including the motor vehicle, clothing, mobile phones and DNA samples have been sent to relevant authorities and a report is not yet received.
