After the murder of presidential candidate Luis Carlos Galán in August 1989, students started a movement calling for a referendum "for peace and democracy" to be held on 21 January 1990. However, under pressure from drug cartels, the government rejected the proposal. The students then set up the "We can still save Colombia" movement, which called for a referendum alongside the general elections on 11 March 1990 on establishing a Constitutional Assembly. The referendum saw 2,235,493 vote in favour and 117,000 vote against.
Following the unofficial referendum, President Virgilio Barco Vargas issued decree 927 on 3 May calling a referendum on electing a Constitutional Assembly alongside the presidential elections on 27 May. Although this was in violation of article 114 of the constitution, which gave Congress sole rights to reform the constitution, the referendum was approved by the Supreme Court.