Article 122. Voting in elections shall be by secret ballot, control over the expression of the will of voters during the voting shall not be allowed. Article 123. The right to nominate candidates shall be exercised in accordance with legislation of Turkmenistan. Article 124. National and local referenda may be held to address the most important issues of state and public life. Decisions taken as a result of a referendum can be cancelled or changed only by a referendum. Article 125. The right to make a decision on holding a national referendum shall belong to the Halk Maslahaty upon the proposal of at least two thirds of the total number of members of the Halk Maslahaty or upon the proposal of at least two hundred and fifty thousand citizens who have the right to vote. Article 126. The right to appoint local referenda shall belong to the Gengesh on its own initiative or at the suggestion of at least one quarter of the voters residing in the relevant territory. Article 127. Referenda shall be held by universal, equal, direct and secret ballot. Citizens of Turkmenistan who have the right to vote shall participate in referenda. Article 128. The procedure for holding elections and referenda shall be determined by law. Elections and referenda shall not be held during the state of emergency and martial law. SECTION VI. PROSECUTOR’S OFFICE Article 129. Supervision over the exact and uniform observance of the laws of Turkmenistan, acts of the President of Turkmenistan, the Cabinet of Ministers of Turkmenistan, resolutions of the chambers of the Milli Gengesh of Turkmenistan shall be entrusted to the Prosecutor General of Turkmenistan and his subordinate prosecutors. The prosecutor shall participate in the consideration of cases in the courts on the grounds and in the manner stipulated by law. Article 130. The Prosecutor’s Office shall oversee the legality of operational investigative activities and the investigation of criminal cases. Article 131. The Prosecutor General of Turkmenistan shall head the unified centralized system of prosecutor’s offices.