There is a strong public interest in rehabilitation, both for the benefit of the community and the individual. This rehabilitation interest may be duly taken into account when deciding whether or not to impose a time limit. If a minimum and an additional penalty are imposed, this may also be taken into account at each stage of the criminal proceedings. For the reasons set out by the Court in R/Moffitt, unpublished, 21 June 1990 and R/Chee Beng Lian of 28 June 1990, rehabilitation capacity is not limited to the minimum duration, to the exclusion of the additional duration or vice versa. The judge must impose a sentence sufficient, but not greater than, what is necessary to: reflect the seriousness of the crime; promote compliance with the law; provide a just sentence for the offence; adequate deterrence of criminal behaviour; protect the public from other crimes committed by the accused; and to provide the defendant with necessary education, training or medical care. Criminal law theorists believe that judgments have two purposes. First, they are intended to deter the convicted person and others who are contemplating the same offence from committing future offences. Second, a sentence is used to retaliate, which postulates that the criminal deserves to be punished for acting criminally. In sentencing, a judge must impose the least severe sentence that achieves these two objectives while taking into account the need for social protection. Retributive theorists claim that individuals are rational beings capable of making informed decisions, and therefore that breaking the rules is a rational and conscious decision. They propose an « offence-based tariff, » that is, « a set of more or less severe penalties adapted to crimes of varying gravity: minor penalties for minor offences, heavier penalties for more serious offences » (Cavadino and Dignan, 2007, p. 44). Although the idea of retaliation as a justification for a criminal sanction often enjoys intuitive support, it has been the subject of various criticisms.

Some critics, for example, have raised questions about the difficulties of ordering or classifying crimes. Is it possible to develop a satisfactory scale of penalties for all crimes? Others question the extent to which crimes are committed by rational actors, arguing that retaliation excessively rationalizes the crime. It has also been suggested that punishing those who have done wrong does not address the underlying causes and social conditions that led to the crime in the first place, and that punishment must include a more rehabilitative approach (Hudson, 2003; Zedner, 2004). Booker simply made the federal guidelines consultative, raising a flood of other questions. In Rita v. United States, 551 U.S. ___ (2007), the Supreme Court clarified that district courts may presume that a sentence imposed that falls within the scope of the Guidelines is appropriate. In Gall v. United States (06-7949) (2008), the Supreme Court upheld the Booker decision and held that trial judges have the power to impose sentences lower than the « mandatory » minimum sentences of the Federal Guidelines, provided they provide reasons for doing so. In Irizarry v. The United States (06-7517) (2008) noted that trial judges may also impose a sentence in excess of the statutory maximum provided by the Guidelines without first informing the defendant that he or she might consider such an increase in sentence.

In Greenlaw v. United States (07-330) (2008), the Supreme Court held that in the absence of an appeal or cross-appeal from the parties involved on the question of appropriateness of a judgment, appellate courts did not have the power to vary a judgment on their own initiative. Why are criminals punished for their crimes? What does the criminal law want to accomplish with sentences for offenders? There are countless answers to these questions, perhaps as many different answers as there are citizens in this country, multiplied by the number of criminals. Society has the right to have the sentence imposed disclose the offender`s criminal conduct and, if the sentence fails to do so, there is an error in the exercise of discretion. Section 3A of the Crimes (Sentencing Procedure) Act 1999 sets out the purposes for which a court may impose a sentence. Since section 3A does not depart from the common law (see below), the starting point for any discussion of sentencing objectives must be Veen v The Queen (No. 2) (1988) 164 CLR 465, where Mason, Brennan, Dawson and Toohey J. 476: Except in well-defined circumstances such as the youth or mental incapacity of the aggressor.

Public deterrence is generally regarded as the primary objective of sentencing, and subjective considerations relating to the prisoner in question (however persuasive) are necessarily subsidiary to the obligation of the courts to ensure that the sentence imposed is an effective factor in preventing the commission of similar crimes by those who might otherwise be tempted by the prospect of: that only a lenient sentence is imposed.