The function of the criminal law is largely to set the parameters within which the criminal justice system operates. There are two aspects to this. Firstly, the criminal justice system is a tool of social control representing the agglomeration of powers, procedures and sanctions which surround the criminal law.


The police are empowered to investigate crime, search for evidence, arrest suspected offenders and question them. The courts are empowered to try persons charged with committing crimes and, if convicted, to sentence them. In setting the parameters within which this coercive State apparatus operates, the criminal law plays a central role; a person may only be arrested where he is suspected of committing a crime; the police may only search for evidence which points towards the commission of a crime; the courts may only try and sentence persons who are charged with, and then convicted of, committing crimes.


It is crucial, therefore to define clearly what acts, omissions or states of affairs amount to crimes as all the other powers, procedures and sanctions of the criminal justice system are dependent upon these definitions. The criminal law, accordingly, limits and controls the legitimate exercise by the State of its coercive power to investigate crime and prosecute, convict and punish criminals. Secondly, the criminal law operates as a guide to the citizen indicating the limits of legitimate activity -on his part and predicting the consequences of infraction of the criminal law.


If the power of the State is to be effectively limited and if the citizen is to be able confidently to make rational choices regarding his behaviour, the criminal law must be clear, relatively stable and accessible, that is, knowable in advance.


Throughout the course of this book judicial decisions on the content and ambit of the substantive criminal law will be subjected to criticism, sometimes trenchant criticism, as there is a tendency for judges to lose sight of the wider role which the criminal law serves in their understandable desire to see persons whom they regard as 'undersirable characters' locked behind bars.


The criminal law is a series of prohibitions backed up with the threat of punishment. An understanding of the function of the criminal law requires further inquiry into the reasons why breaches of the criminal law are met with punishment and why certain behaviour is subjected to prohibition.


Social control and social morality


The criminal law represents the rules of social control within a society. But how are the rules determined? Is there an essential criterion which determines which behaviour merits criminal sanction? The Wolfenden Committee, Report of the Committee on Homosexual Offences and Prostitution (1957), stated (at paras. 13 and 14) that the function of the criminal law is:1. to preserve public order and decency, 2. to protect the citizen from what is ' offensive or injurious and 3. to provide sufficient safeguards against exploitation or corruption of others, particularly those who are specially vulnerable because they are young, weak in body or mind or inexperienced or in a state of special physical, official or economic dependence. It is not... the function of the law to intervene in the private lives of citizens, or 4. to seek to enforce any particular pattern of behaviour, further than is necessary to carry out the purposes we have outlined.


To this extent the criminal law is a reflection of corporate or societal morality. The wrong-doing which the criminal law seeks to punish is that which threatens the fundamental values upon which a society is founded. While it is harmful to the individual to be robbed or assaulted, it is also harmful to society as such behaviour threatens the security and well-being of that society. The criminal sanction operates then as a form of social control both punishing the offender and re-asserting the mores of that society.



A major purpose which punishment serves is retribution. Punishment is meted out to the offender because this is what he deserves in response to his infraction of the criminal law. This was expressed by Stephen, A History of the Criminal Law(1883)at pp. 81-82: the infliction of punishment by law gives definite expression and a solemn ratification and justification to the hatred which is excited by the commission of the offence, and which constitutes the moral or popular as distinguished from the conscientious sanction of that part of morality which is also sanctioned by the criminal law. The criminal law thus proceeds upon the principle that it is morally right to hate criminals, and it confirms and justifies that sentiment by inflicting upon criminals, punishments which express it.    To some extent, therefore, retribution reflects society's desire for vengeance. When people join together in a society governed by law, they relinquish their own right to retaliate to harm done to them in exchange for the protection which the law offers them. H. Gross gives expression to this view in A Theory of Criminal Justice (1979) (at pp. 19-20): But society requires that this right [to repay harm with harm] be surrendered by its members, and in exchange undertakes to protect them by laws that can be effective only if violations are punished. The bargain that is struck, then, places a moral obligation on society to punish crime as it places a moral obligation on its members to refrain from breaking the law.


Vengeance or retaliation is only one aspect of retribution. A further element is that of denunciation. The infliction of punishment signals society's disapproval of the criminal's conduct and reaffirms the values the criminal law is designed to uphold. This reflects the more modem view of the appropriate place for retribution in the criminal justice system. In Sargeant (1974), a case concerning violent crime, Lavvton LJ, after rejecting the idea of'an eye for an eye', gave expression to this view (at p. 77): society, through the courts, must show its abhorrence of particular types of crime, and the only way in which the courts can show this is by the sentences they pass.


The courts do not have to reflect public opinion. On the other hand they must not disregard it. Perhaps the main duty of the court is to lead public opinion. Anyone who surveys the criminal scene at the present time must be alive to the appalling problem of violence. Society, we are satisfied, expects the courts to deal with violence... Those who indulge in the kind of violence with which we are concerned in this case must expect custodial sentences.


The punishment inflicted, however,.must not represent a blind act of vindictive retaliation; it must be both reasoned and reasonable. The idea which has gained ascendancy in recent years is that of 'just deserts' based on the philosophical ideas of Kant.


A person who commits a crime has gained an 'unfair advantage over the other members of society. Punishment cancels out that advantage (particularly where the court orders confiscation, restitution or compensation) while, at the same time, it re-affirms the values of that society by visiting moral disapproval or reprobation on the offender. The punishment the criminal deserves, of course, must bear some relationship to the harm he has caused. Punishment can only be considered reasonable where the courts respect the concept of proportionality.



A second purpose which punishment may serve is that of deterrence, whether  this be particular deterrence (i.e. dissuading the individual criminal from re-offending in the future) n general deterrence (i.e. dissuading other possible offenders from offending by the example made of each particular offender). It is difficult to assess the effectiveness of individual deterrence.


Some offenders may never offend again even if they are not caught or punished; others may only be deterred where the punishment imposed is so severe that it is out of all proportion to the gravity of the wrongdoing. In relation to general deterrence, courts, in the past, sometimes imposed exemplary sentences to deter others where an offence had become prevalent or was particularly grave. While judges may have associated severe sentences with deterrence, the connection was not necessarily valid. In The Sentence of the Court (5th edn, 1990) published by the Home Office, it is stated (at para. 3.3):


The simplest way of evaluating the individual deterrent effect of sentencing is to compare the proportions, of offenders undergoing different types of sentence who, when free to do so, continue to commit offences. The almost invariable conclusion of the large amount of research which has been undertaken... is that it is hard to show any effect that one type of sentence is more likely than any other to reduce the likelihood of reoffending, which is high for all. Similarly, longer periods of custody or particular institutional regimes do not seem to have a significant effect. Studies comparing the reconviction rates of offenders given community service orders with those given custodial sentences have also shown little difference.


Different sentences therefore have little effect in deterring offenders. The Sentence of the Court goes on to state, however, (at para. 3.4.) that: The inference most commonly drawn from research studies is that the probability of arrest and conviction is likely to deter potential offenders whereas the perceived severity of the ensuing penalties has little effect. Of course, detection and conviction must result in punishment if the rules are not to lose their coercive force.


Thus, the deterrent role of the criminal process is a limited one; those who are set on committing crime may not be deterred by the criminal law. For most members of society, however, the criminal law may serve to educate them on acceptable and unacceptable conduct creating thereby unconscious inhibitions against offending.