Witnessing the atrocities committed by the M23 during its occupation of the city of Goma and the city of Sake from 20 to 22 November 2012, in this study we analyse the period of occupation of the city of Goma and the city of Sake by the M23 and suggest possible solutions to contribute to the construction of a State of Law because justice raises a nation. During the occupation, M23 combatants committed serious violations of IHL against the civilian population and members of the FARDC who surrendered and no longer participated in hostilities. The violations committed included killings, rapes, forced labour, recruitment and use of children, cruel, inhuman or degrading treatment and violations of the right to property (widespread looting of public and private property), violations of the right to a fair trial. As an occupying power, the M23 was only a temporary administrator and had several obligations towards the civilian population under its occupation but also responsibilities in case of violation of legal instruments at the national, regional and international level.