Ouko did not introduce siasa. It is siasa that was brought into his reports by the politicians. When Ouko questioned the Eurobonds he was called names. Now we have to pay back and no one can tell us where the money went to. Apart from the Eurobond saga, Ouko's reports were just objective like the current Auditor General's.
Mind you, nobdy seems to care about those reports any more. Read the current one on the billions wasting away at the stores of GDC and I can assure you there will be no consequences.
The quality of their reports nowadays is commendable and they have avoided siasa that Ouko introduced.