[4] On September 16, 2020, Mustafayev was sentenced by a Russian military court to fourteen years in a strict regime penal colony.
[5] The Russian civil rights society Memorial has included Server Mustafayev in the "Support program for political prisoners".
[2][6] According to Human Rights Watch the sentenced prison terms against Mustafayev and six other Crimean Tatars are part of a pattern of politically motivated prosecutions that have been happening since the annexation of Crimea by the Russian Federation.
[7] In June 2018 the European Parliament adopted a resolution in which it demands Russian authorities to immediately and unconditionally release illegally detained Ukrainian citizens including Server Mustafayev.
[8] The United States Mission to the Organization for Security and Cooperation in Europe declared its concern about the health conditions of Crimean Tatar political prisoners, including Server Mustafayev and called for his release.