Who administers direct democracy mechanisms at the national level?

THEREFERENDUM ACT, 2013

http://www.parliament.go.tz/assets/uploads/files/47716-A-BILL---THE-REFERENDUM-.pdf

CONDUCT OFREFERENDUM

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5.-(1)   Without prejudice  to  the provisions  of  the National Elections  Act,  the Commission  shall  be responsible for-

(a)  supervision of   the  general conduct  of  a referendum; and

(b)  promotion and regulation of voters’ educationfor the referendum.

 (2)  During  the  conduct of  a  referendum, the Commission  shall  not be  subject  to the  direction  or control of any person or authority.

 (3)  Where  the  issue for  a  referendum is  a  union matter, the  Commission  shall, in  exercising  the powers conferred  to  it by  this  section, act  in  collaboration with the Zanzibar Electoral Commission.