The article covers the practice of the European Court of Human Rights in the sphere of lawful detention of five categories of individuals, who are referred to in Article 5(1) (e) of the European Convention for the Protection of Human Rights and Fundamental Freedoms of 1950. The authors study the purposes and criteria of detention of infected persons, persons of unsound mind, alcoholics, drug addicts, and vagrants. In addition, the authors study the opinions of Russian experts on this issue. The conclusion is that under Article 5(1) (e) of the Convention, lawful detention implies the measures to not only isolate a person from society but also to reduce his/her danger to himself/ herself or the public.