"In my opinion the trial judge following upon a conviction on a retrial must, when he comes to sentence, exercise his own judgment and his own discretion. He will do that having regard to the offence committed; to the circumstances of its commission; to the antecedents of the convicted person and to all other relevant facts which are personal to him. In addition he will have regard to the sentence imposed upon the first conviction and he will be conscious of the principle, so-called, 'that unless there is some strong ground there should not be a disparity between the sentence imposed upon persons convicted on the second occasion after a retrial compared with those that were imposed upon them on the first occasion'. ... That principle is based upon policy. The policy consideration underlying the specification of the upper limit on the sentence is twofold. In the first place, a person whose conviction is tainted in that the first trial was defective to an extent not capable of being saved by the proviso, should not, in fairness, be required to run any risk of suffering a heavier sentence on a new trial as a consequence of exposing on appeal the defective nature of the first trial. It is in the public interest in ensuring orderly and proper administration of the criminal law that defects in trials should be challenged and laid bare on appeal. As a corollary to this, it is wrong that any person should suffer ill-founded criminal judgment in consequence of a defective trial, and feel constrained to avoid exposing that defect lest on a new trial a heavier sentence be passed. In the second place, the passing of a heavier sentence on a new trial could be seen as by the convicted person, as well, perhaps, by others in the community at large, as possibly importing some element of retribution by the machinery of criminal justice in consequence of the conviction on the first trial having been successfully overthrown. Any such impression would, of course, be groundless. But at the same time it is highly desirable to avoid any possible basis for permitting the operation of the system to be exposed to criticism of such a nature. But if having had regard to the first sentence and the policy considerations to which I have referred, as the trial judge in this case did, and to all other facts relevant to sentence, the sentencing judge is of the opinion that the sentence passed following upon the first conviction was inadequate or inappropriate, then he must act upon that opinion because it is at that point of his judgment which is decisive and it is a judgment which he must make and act upon."