“Counsel for the appellant laid great stress on what he submitted was the inevitable unfairness to the defendant if a trial were to begin in his absence after he had absconded. His legal representatives would be likely to regard' their retainer as terminated by his conduct in absconding. Thus there would be no cross-examination of prosecution witnesses, no evidence from defence witnesses, no speech to the jury on behalf of the defendant. The judge and prosecuting counsel however well intentioned could not know all the points which might be open to the defendant. The trial would be no more than a paper exercise and almost inevitably lead to conviction. The answer to this contention is that one who voluntarily chooses not to exercise a right cannot be heard to complain that he has lost the benefits which he might have expected to enjoy had he exercised it. If a defendant rejects an offer of legal aid and insists on defending himself he cannot impugn the fairness of his trial on the ground that he was defended with less skill than a professional lawyer would have shown. If, after full professional advice he chooses not to exercise his right to give sworn evidence at trial he cannot impugn the fairness of his trial on the ground that the jury never heard his account of the facts. If he voluntarily chooses not to exercise his right to appear he cannot impugn the fairness of the trial on the ground that it followed a course different from that which it would have followed had he been present and represented.”