One argument that Mill develops further than any previous philosopher is the harm principle.
The harm principle holds that each individual has the right to act as he wants, so long as these actions do not harm others.
In contrast Mill does not support legal penalties unless they are based on the harm principle.
He does argue, however, that individuals are prevented from doing lasting, serious harm to themselves or their property by the harm principle.
The second is that, regardless of the harm principle, criminal liability for attempts can be justified in utilitarian terms.
Humboldt outlined an early version of what Mill would later call the "harm principle".
As in classical liberalism, the harm principle comes into play.
These problems are equally prevalent when the harm principle is applied to insider dealing.
An offense meets the harm principle only if it is a wrong and also causes harm.
In criminology, the de minimis or minimalist approach is an addition to a general harm principle.