Mexico City
In response to the demands, in 1987 the Federal District received a greater degree of autonomy, with the elaboration the first Statute of Government (Estatuto de Gobierno), and the creation of an Assembly of Representatives.[citation needed] In the 1990s, this autonomy was further expanded and, starting from 1997, residents can directly elect the head of government of the Federal District and the representatives of a unicameral Legislative Assembly (which succeeded the previous Assembly) by popular vote.
What gave the Federal District more autonomy? 
first Statute of Government
In response to the demands, in 1987 the Federal District received a greater degree of autonomy, with the elaboration the first Statute of Government (Estatuto de Gobierno), and the creation of an Assembly of Representatives.
the Federal District