Introduction to Criminal Law

Note on Introduction to Criminal Law by Legum

Introduction to Criminal Law:

To understand criminal law, it is essential to understand the following:

1. In any society, there are a range of individual and collective conducts that either benefits the society or harms the society.

2. Whilst some harms are marginal or has negligible effects, some harms have substantial impacts on society, and others even threaten the very existence of the society. For instance, society needs a population, and killing people diminishes the population.

3. Every society determines which conducts are harmful to it, and seeks to prevent those conducts.

4. Criminal law represents one of the tools for achieving the end of preventing the commission of harmful conducts. It does this by defining what is prohibited (called crime), specifying punishment for those who engage in what is prohibited, how the guilt of those who are believed to have engaged in a prohibited act should be determined, inter alia.

Some Scholarly Definitions of Criminal Law:

According to Norton (2020), criminal law is “the body of law that defines criminal offenses, regulates the apprehension, charging, and trial of suspected persons, and fixes penalties and modes of treatment applicable to convicted offenders.”

According to Vuleta (2022), criminal law is also known as penal law and represents “the body of law that defines crimes and sets out punishments. It is concerned with preventing and punishing criminal behaviour and is distinct from civil law, which deals with private disputes between individuals.”

Evidently, both definitions acknowledge that criminal law is concerned with, among others, the definition of crimes. In criminal law, a crime is an act or omission recognized by the laws of a state as an offence and for which punishment is provided. In the case of Republic v Yebbi and Avalifo it was stated that “every crime is an offence against the State.” Acts such as murder, rape, robbery, are considered offences against the state, and are duly punished.

Functions of Criminal Law:

Criminal law has several functions. The Wolfenden Report of 1957 provides a good starting point. In 1957, and following the convictions of several persons for acts of homosexuality, a committee, known as the Wolfenden Committee, was setup to inquire into the legality of homosexuality and prostitution. In its report, the committee stated that the function of the law is “ to preserve public order and decency, to protect the citizen from what is offensive or injurious, and to provide sufficient safeguards against exploitation and corruption of others ...”

Beyond the broad functions of criminal law as stated in the Wolfenden report, an examination of criminal code of various states reveals some specific functions of criminal law. For instance, an examination of the criminal code of Ghana (Act 29) reveals that it seeks to protect property, protect and preserve human lives, protect people from sexual abuse, promote public order, promote administrative justice, protect public health and morality, prevent unreasonable harm to animals inter alia.

Sources of Criminal Law:

The laws of a state stipulate the sources of its criminal law. Some laws give validity to some other laws as sources of criminal law; some laws exclude other laws from being sources of criminal law; and some laws provide specific provisions on the constitutive elements of crimes among others.

In Ghana, the 1992 constitution is a source of criminal law because it defines certain acts as offences and provides punishment for persons who commit the offence. For example, article 3(3) of the 1992 constitution provides that anyone who “by himself or in concert with others by any violent or other unlawful means, suspends or overthrows or abrogates this Constitution or any part of it, or attempts to do any such act…”, commits an offence of high treason and if convicted, be sentenced to suffer death.

In addition, the 1992 constitution also gives validity to other sources of law which may create new sources of criminal law. In article 11 of the 1992 constitution for instance, the constitution itself is considered a source of law, in addition to acts of parliament, rules or orders made by an authority under a power conferred by the constitution. The Criminal Code of 1960 (Act 29) for instance, is an act of parliament meant to “consolidate and amend the law relating to criminal offences” and is thus a key source of criminal law in Ghana.

Whilst customary law and the common law are acknowledged as sources of Ghanaian law per article 11 of the 1992 Constitution of Ghana, offences under customary law or under the common law are not necessarily offences in Ghana unless the definition of those crimes are specifically adopted as offences by the state. The criminal code in Ghana (Act 29) in section 8 excludes the common law from being the basis for punishment by providing that “no person shall be liable to punishment by the common law for any act.”

The express statutory exclusion of the common law as a source of criminal law in Ghana, prevents the courts in Ghana from relying on the common law for definitions of offences or for “creating offences”. In the case of Shaw v DPP, and without the existence of an explicit provision excluding the common law as a source of criminal law, it was held that conspiracy to corrupt public morals was an offence under the common law and that the courts have “a residual power, where no statute has yet intervened to supersede the common law, to superintend those offences which are prejudicial to the public welfare”. The express exclusion of the common law as a source of criminal offences takes away this residual power from Ghanaian courts and prevents them from relying on the common law as a source of criminal law.

On customary offences not necessarily being offences under the laws of Ghana, the case of Debrah v the Republic is an authority. In Debrah v the Republic, a District Court found Debrah, the accused, guilty of insulting the chief of Kadjebi contrary to section 53 of the Chieftaincy Act (Act 370). The accused person was found to have collected stone particles on the road close to the chief’s palace and to have spoken directly to the chief of Kadjebi, acts considered offensive in Kadjebi customary law. Upon appeal of the ruling of the District Court to the High Court, the court allowed the appeal and stated that

It was a fundamental right of every citizen that he could not be punished for any offence which had not been directly set out and the punishment thereon equally laid down in the relevant statutory instrument… Hence, for any customary offence to be punishable, steps had to be taken to have such offences and their punishment clearly spelt out in the relevant statutory instrument.

Clearly, the fact that an act is an offence in customary law does not necessarily make it a crime in Ghana.

Some Basic Language of Criminal Law:

1. A Suspect: When a person is suspected or believed to have committed a crime, but has not yet being found guilty of committing the crime or brought before the court for prosecution, he or she is known as a suspect.

2. An Accused Person: When a suspect is arraigned or brought before the court in compliance with criminal procedure, he or she becomes an accused person.

3. A Convicted Person: When an accused person is found guilty of a crime after criminal proceedings, he or she is deemed to have been convicted.

4. Criminal Proceedings: These are the judicial processes through which the guilt of a person suspected to have committed is determined.

5. Crime: Per section 1 of Act 29, a crime is “any act punishable by death or imprisonment or fine".


This note discussed criminal law in terms of scope and functions, sources of criminal law, and some basic and frequently used terms in criminal law especially in the Ghanaian context.


Norton, J. and Jescheck, . Hans-Heinrich (2020, February 27). criminal law. Encyclopedia Britannica.

(Vuleta, 2022)

Vuleta, B. (2022, August 10). Criminal Law: Definition and History. Retrieved from Legal Jobs: