What kind of law is criminal law, and how to study it

Criminal law is the subject everyone thinks they already know. You have watched the dramas, you know what a verdict sounds like, and then the first problem question hands you three defendants, a borrowed bicycle and a punch that may or may not have been self-defence. Suddenly the television has nothing useful to say.

So start with the question students type first: what kind of law is criminal law? It is public law. The state prosecutes, and the question is whether the defendant is liable for an offence. Once you see that every offence breaks into parts and every defence works as a test, you know how to study criminal law on the LLB. This guide takes University of London LLB students through both.

So what kind of law is criminal law?

Criminal law is public law. A crime is treated as a wrong against the community, so the case is brought by the state, not by the person who was hurt. The question at the end is liability: did this defendant commit this offence, and if so, does a defence apply? If the offence is proved and no defence applies, the defendant is convicted and the court can punish.

Compare contract law. As we set out in what kind of law contract law is, a broken contract is a private dispute: one party sues the other for a remedy, and nobody is prosecuted for failing to deliver a sofa. The same facts can raise both, of course. A seller who pockets the deposit and vanishes may face a civil claim and a theft charge, and each is answered by different rules.

Criminal law is also one of the first subjects you meet. The University of London's LLB programme specification for 2025-26 sets four compulsory modules at Level 4 of the Standard Entry LLB, and its Level 4 exit award, the Certificate of Higher Education in Law, covers "the core principles of Public law, Contract law and Criminal law".

What the criminal law module tests

The same specification says what students at that stage should be able to do: "identify the relevant legal issues arising from factual situations" and "identify and apply case law and statutes relevant to the identified legal issues". In criminal law, that means problem questions where you work out which offences the facts raise, whether each element is proved, and whether a defence gets the defendant off.

On assessment, the specification says modules are assessed "by examination only or by an examination element and a Multiple Choice Question (MCQ) element", with the details for each module in its module descriptor on the VLE. Check yours there rather than trusting a forum post from three years ago.

The good news is that one method handles all of it.

Every offence is a set of elements

Every offence has a conduct element (actus reus: what the defendant did, and sometimes the circumstances or result) and a fault element (mens rea: the defendant's state of mind). The prosecution must prove both. Learn an offence as a list of its elements and you have a checklist to run against any set of facts.

Theft shows how it works. Section 1(1) of the Theft Act 1968 says a person is guilty of theft "if he dishonestly appropriates property belonging to another with the intention of permanently depriving the other of it". Split that sentence and you get five elements:

• Appropriates (conduct): under section 3(1), "any assumption by a person of the rights of an owner".
• Property (conduct): defined in section 4.
• Belonging to another (conduct): under section 5(1), this includes anyone with possession or control of it, or a proprietary right or interest in it.
• Dishonestly (fault): section 2(1) lists three beliefs that mean an appropriation is not dishonest, including a belief that you have the legal right to deprive the owner.
• Intention of permanently depriving (fault): section 6(1) stretches this to treating the thing as your own to dispose of regardless of the owner's rights, and to a borrowing that is equivalent to an outright taking.

Here is a short hypothetical. Priya takes Tom's bicycle from outside the library, rides it home and sells it the next day. Appropriation, property and belonging to another are quickly dealt with. The marks sit in the fault elements: did she believe Tom would have consented, and does selling it show an intention to treat it as her own to dispose of? Each element gets a sentence, and the contested ones get the analysis.

Our free criminal law crib sheet covers the offences and defences across the syllabus, from homicide to criminal damage, with a quick-reference table of leading authorities. It is free with a free account.

Every defence is a test

Defences reward the same habit. Self-defence is a series of questions a court actually asks, and a general sense that the defendant was only protecting themselves answers none of them.

Section 76 of the Criminal Justice and Immigration Act 2008 sets out how to decide whether the force used in self-defence was reasonable. Turned into steps for an exam answer:

1. What did the defendant believe the circumstances were? Under section 76(3) reasonableness is judged "by reference to the circumstances as D believed them to be".
2. Was that belief genuinely held? Under section 76(4) a genuine belief counts even if it was mistaken, and even if the mistake was unreasonable, although how reasonable it was helps decide whether it was genuine.
3. Was the mistake caused by voluntary intoxication? If so, section 76(5) says the defendant cannot rely on it.
4. Was the force proportionate in those circumstances? Outside a householder case, force that was disproportionate is not reasonable (section 76(6)); in a householder case, force that was grossly disproportionate is never reasonable (section 76(5A)).

Every general defence on the syllabus can be learned this way: the conditions, in order, with the authority for each. A defence learned as a test gives you the structure of the paragraph before you write it.

Common exam traps

In our experience, the same few habits cost criminal law students the most marks.

• Jumping to the defence. Self-defence only matters once the offence is made out. Prove the conduct and fault elements first.
• Merging the elements. "She clearly stole it" earns nothing on its own. Take the elements one at a time and spend your words where the facts are arguable.
• Forgetting the second defendant. Problem questions often have several people in them. Each one needs their own offences and their own fault.
• Retelling cases. State the rule and apply it to your defendant. The examiner does not need the full story of the case.

Each one is a problem of applying the law under time, which reading alone will not fix. You fix it by writing answers.

Questions students ask

What kind of law is criminal law?

Criminal law is public law. A crime is treated as a wrong against the community, so the state prosecutes rather than the victim, and the question is whether the defendant is liable for an offence. Liability needs the offence's conduct and fault elements to be proved, with no defence applying. On the University of London LLB, criminal law is one of the core subjects at Level 4, alongside public law and contract law.

Is criminal law hard on the LLB?

It rewards precision. The programme specification expects Level 4 students to identify the legal issues in a set of facts and apply case law and statutes to them. In criminal law that means knowing each offence element by element and each defence as a test, then applying them to several defendants at once. It feels hard until you have a method, and then it feels like a checklist.

What is the difference between criminal law and civil law?

Criminal law deals with offences against the community: the state prosecutes, and a defendant found guilty can be punished. Civil law, which includes contract and tort, deals with disputes between private parties: the person wronged sues and asks for a remedy, usually money. The same facts can raise both, such as a seller who takes a deposit and disappears, but each case runs under its own rules.

Try it on a real question

The quickest way to find out whether your elements and tests hold up is to answer a problem question. Criminal law is a Year 1 subject, and our criminal law subject page offers a free trial mock exam: submit a practice answer, get AI-marked feedback, no payment required. It is feedback on a practice answer, not an official mark.