Samuel Kinyanjui was accused of killing the late Dr. Gakuru through reckless driving following an accident that claimed the life of the Governor.
Mr Kinyanjui will be arraigned in a court in Kigumo and could be charged with one count of murder.
Dr Gakuru died on Tuesday last week while receiving medical attention at the Thika Level 5 Hospital following a grisly road accident near Kabati.
Mr Kinyanjui, recounted how the horror crash unfolded seconds before the car smashed into the guardrail which tore through the vehicle.
He recalled the Governor shouting "God", but his cry was drowned by the screeching tyres and sounds of metal tearing apart.
The driver had earlier on stated that the accident happened as he was trying to prevent a multiple cars' accident. He further recounted the last moments of the governor, recalling how Dr Gakuru sat in the car bleeding for over 40 minutes as he waited for help.
SEE ALSO: KALONZO finally speaks on whether he is planning dump RAILA ODINGA for UHURU/ RUTO this weekThe driver stated that he watched helplessly as Mr Gakuru, who was trapped in the wreckage, groaned in pain seeking assistance.
Dr Gakuru was traveling to Nairobi at 5:30am for an interview with a local TV station. The former Governor, who was in office for only 90 days, will be laid to rest on Saturday November 18.