Practice Relating to Rule 88. Non-Discrimination
Section D. Persons deprived of their liberty
Switzerland’s Basic Military Manual (1987) recalls: “No adverse distinction can be based on race, nationality, religion, political opinions, language, colour, social condition, birth or other similar criteria.”
Switzerland’s Regulation on Legal Bases for Conduct during an Engagement (2005) states:
Prisoners must be humanely treated at any time and in any place. Any act of torture, physical or mental ill-treatment, degrading treatment or discrimination as well as measures of reprisal are prohibited. The State is responsible for the treatment of prisoners; each individual may be held liable for violations.
[emphasis in original]
In 2010, in its Report on IHL and Current Armed Conflicts, Switzerland’s Federal Council stated:
3.4 [Increasing use] of anti-guerrilla tactics
Apart from the direct fight against insurgents, international humanitarian law also addresses other anti-guerrilla tactics. … If members of militias or opposition groups fall into the hands of the government they benefit from the protection of art. 75 of [the 1977] Additional Protocol I as well as that of art. 3 common to the  Geneva Conventions.
[footnotes in original omitted]
In 2012, Switzerland’s Federal Department of Foreign Affairs issued a press release entitled “Appeal by the Swiss authorities for compliance with international humanitarian law in Syria”, which stated: “Persons who are not or no longer taking part in the hostilities must be treated humanely without any discrimination. This is especially important in the case of detainees.”