If, therefore, two children of eleven engage in mutual misconduct, they incur no liability to legal punishment. But two boys of thirteen are liable to prosecution for the practice of mutual masturbation. Each of them has performed an improper act with a child under fourteen years of age, and the liability to punishment in each case depends upon the answer to the question whether the offender possessed sufficient knowledge to enable him to understand his culpability. This knowledge is not identical with the knowledge that the offence was legally punishable; that is to say, either boy would be liable to punishment, even though he had no idea whatever that improper sexual relations with children under fourteen constituted an offence against the law. All that is necessary is that he should possess a sufficient degree of intelligence to understand his culpability, which is quite another thing from his possessing knowledge of his legal liability to punishment. Generally speaking, however, the public prosecutor is disinclined to initiate proceedings in such cases, for the most part because it is held that the necessary understanding of culpability is commonly lacking. But such prosecutions have more than once occurred. In the year 1899, in a little town in the Mark of Brandenburg, proceedings were taken against eighteen school-children, boys and girls, and five pupil-teachers. These twenty-three persons, who appeared in the dock, had all reached an age at which they became liable to criminal prosecution; in the case of a number of other boys and girls who were concerned in the affair, no prosecution could take place. Ultimately, all the accused were discharged, as it was held that when the offence was committed they did not possess the requisite understanding of its culpable character. But by order of the court several of the accused were transferred to a reformatory. Since a prosecution may take place in such cases, a conviction is also possible. It is evident that as soon as a child is twelve years old, it may incur legal liabilities in consequence of the activity of the sexual impulse.