European Convention on Human Rights - Article 4

Article 4 – Prohibition of slavery and forced labour

1 No one shall be held in slavery or servitude.

2 No one shall be required to perform forced or compulsory labour.

3 For the purpose of this article the term "forced or compulsory labour" shall not include:

a any work required to be done in the ordinary course of detention imposed according to the provisions of Article 5 of this Convention or during conditional release from such detention;

b any service of a military character or, in case of conscientious objectors in countries where they are recognised, service exacted instead of compulsory military service;

c any service exacted in case of an emergency or calamity threatening the life or wellbeing of the community;

d any work or service which forms part of normal civic obligations.

Carta dei diritti fondamentali dell’Unione europea