It's a general principle in criminal cases (in Australia) that you get a 25% discount on penalty for an early guilty plea, because it prevents resources being expended on the prosecution case. That 25% diminishes the later you enter the plea, because of the resource allocation required by the prosecution that becomes wasted if the guilty plea is entered at a later time. It's got nothing to do with the judge's view on the guilt or innocence of Kerr.
