The law assumes that people are able to control their behaviour and that therefore they can be held responsible for their actions. There are some exceptions to this general rule, notably cases of self-defence, force majeur and insanity. But in general, when none of these exceptions are claimed by the defendant, courts presume responsibility of offenders. For the attribution of legal responsibility, it is not necessary that the perpetrator had a specific intention to cause harm or even was conscious of the possible negative consequences of his (or her) actions. It is sufficient to establish somehow that the perpetrator should have thought of the harm that he might inflict on his victim. Drunken driving is a clear example. When a drunken driver causes another person to die in a car accident, there usually has been no criminal intent to kill nor – probably – a clear awareness of the likelihood of a fatal accident. Still, the driver should have realised when he began drinking that later on he would be unable to drive. This should have led him either to refrain from drinking or organise some other way of transportation afterwards. Negligence is the most important case of legal responsibility for harm that was never intended.

People are held particularly responsible for acquitting themselves of their specific duties. A failure in this respect may lead to responsibility for the consequences, even if those consequences were highly unpredictable. Failing to do one's explicit duty is a severe form of negligence. The signal man who fails to throw a switch in time because at that very moment he happened to be engaged in rescuing a child, thereby causing the death of many train passengers, is still considered to have been negligent because he failed to do his promised duty (Sims, 1883).

Psychological theories about the control of one's behaviour are far more complicated than beliefs on the subject commonly held by lawyers. All classical theories assume that there are different levels of behaviour with more or less behavioural control. At the lowest level of this graded set, there is usually something like reflexes, automated behaviour, or preconscious behaviour. ‘Consciousness,’ Timothy Wilson recently wrote, ‘is a limited-capacity system, and to survive in the world people must be able to process a great deal of information outside awareness‘(Wilson, 2002, p. 8).