The article presents the proceedings of the popular initiative „Expulsion of foreign citizens” that was launched by Swiss People’s Party. The initiative aimed in contributing to internal security threatened by the criminality of foreigners in Switzerland by the controversial idea of expulsion of foreign criminals. The author presents the main idea and arguments of the Swiss People’s Party. The paper presents the background of the initiative and its development. In this case even a counter-proposal was prepared by the Federal Council. The whole process led to the final stage that was the adding of 4 extra paragraphs to art. 121 of Federal Constitution in 2010. The case of this initiative presents how vulnerable society can be to popular arguments not necessary confirmed by scientific research. In consequence of this amendment the expulsion obligation was introduced into Swiss criminal Code. It was a new penal measure that as a rule is obligatory. Some exceptions are possible under extraordinary circumstances. This federal regulation is strict and poses an important question concerning even the violation of human rights.