Issues excluded from being the subject of referendums at the national level

Constitution of the Republic of Latvia (lastamended in 2005)

http://www.wipo.int/wipolex/en/text.jsp?file_id=190856

73. The Budget and laws concerning loans, taxes,customs duties, railroad tariffs, military conscription, declaration andcommencement of war, peace treaties, declaration of a state of emergency andits termination, mobilization and demobilization, as well as agreements withother nations may not be submitted to national referendum.