Doli incapax

The defense of infancy is a form of defense known as an excuse so that defendants falling within the definition of an "infant" are excluded from criminal liability for their actions, if at the relevant time, they had not reached an age of criminal responsibility. After reaching the initial age, there may be levels of responsibility dictated by age and the type of offense committed.

Under the English common law the defense of infancy was expressed as a set of presumptions. A child under the age of seven was presumed incapable of committing a crime. The presumption was conclusive, prohibiting the prosecution from offering evidence that the child had the capacity to appreciate the nature and wrongfulness of what he had done. Children aged seven to under fourteen were presumed incapable of committing a crime but the presumption was rebuttable. The prosecution could overcome the presumption by proving that the child understood what he was doing and that it was wrong. Children fourteen and older were presumed capable of committing a crime. However, the child could rebut this presumption by establishing that because of his immaturity he was incapable of understanding what he had done or the wrongfulness of his conduct.

Governments enact laws to label certain types of activity as wrongful or illegal. Behaviour of a more antisocial nature can be stigmatized in a more positive way to show society's disapproval through the use of the word criminal. In this context, laws tend to use the phrase, "age of criminal responsibility" in two different ways:

Thus, each state is considering whether any given child has committed an offense, and given that answer, what the most appropriate measures would be for dealing with a child who has done what this child did. It is noted that, in some states, a link is made between infancy as a defense and defenses that diminish responsibility on the ground of a mental illness. Distinctions between children, young offenders, juveniles, etc. are used to denote matching levels of incapacity. The majority view is that this linkage is not constructive in that it implies that children are in some way mentally defective whereas they merely lack the judgment that comes with age and experience.

This is an aspect of the public policy of parens patriae. In the criminal law, each state will consider the nature of its own society and the available evidence of the age at which antisocial behaviors begins to manifest itself. Some societies will have qualities of indulgence toward the young and inexperienced, and will not wish them to be exposed to the criminal law system before all other avenues of response have been exhausted. Hence, some states have a policy of doli incapax (i.e. incapable of wrong) and exclude liability for all acts and omissions that would otherwise have been criminal up to a specified age. Hence, no matter what the infant may have done, there cannot be a criminal prosecution. However, although no criminal liability is inferred, other aspects of law may be applied. For example, in Nordic countries, an offense by a person under 15 years of age is considered mostly a symptom of problems in child's development. This will cause the social authorities to take appropriate administrative measures to secure the development of the child. Such measures may range from counseling to placement at special care unit. Being non-judicial, the measures are not dependent on the severity of the offense committed but on the overall circumstances of the child.

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