In March and April 2015 millions of protesters took to the streets during the 2015 protests in Brazil against Rousseff's alleged involvement in the Petrobras scandal which involved kickbacks and corruption. When allegations surfaced that graft occurred while President Rousseff was part of the board of directors of Petrobras, between 2003 and 2010, Brazilians became upset with the government and called for Rousseff's impeachment. No direct evidence implicating Rousseff in the scheme has been made public, and she denies having any prior knowledge of it.