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In general, for a criminal conviction to succeed there needs to be a demonstration of culpability. On the whole, the accused will culpable if at the time of the offence

• he or she was not exempt from liability; for example, the perpetrator may be exempt if below the age of criminal consent (see: Exemption from criminal liability);
• the act which is the subject of the prosecution (see: Actus Reus) is properly attributable to the accused; for example, the accused may not be culpable if the act was indirectly caused by someone else. If the act was involuntary (see: Automatism), this also is a defence.
• the accused must have had a mental state commensurate with the carrying out of the act, at the time of the act (see: Mens Rea). The state of mind may reflect an Intention to cause harm, or a reckless disregard for the fact that harm may result.
• the accused has no General defence (self defence, protection of another person, etc.) or special defennce.

Although it is illogical, English law reflects the feeling in society that the degree of culpability is proportional to the degree of harm. Suppose, for example, that a person fires a gun into a crowded room, with the intention to kill someone. Most people would say that a more serious crime has been committed if someone actually gets killed, than if the bullet hits a pot plant. For a more detailed discussion, see: Subjective and objective culpability.