Who administers direct democracy mechanisms at the national level?

Constitution 1983

Article 69 (2). It shall be the duty of the High Electoral Council composed of judges, to take and cause to be taken all necessary action for the orderly administration and fairness of the elections and referenda from beginning to the end, to examine and give a final decision, during and after the election or referendum, on all irregularities, complaints and objections on matters concerning the elections and the referenda and to accept the election records of the President of the Republic and of deputies.