Cobos, as Vice President and President of the Argentine Senate, cast the deciding vote rejecting an increase in grain export taxes. This controversial bill had led to economic and social instability in Argentina, with mass protests both for and against the government. Cobos had been expected to back President Fernández de Kirchner. "I think today is the most difficult day of my life", Cobos said. "They tell me I must go along with the government for institutional reasons, but my heart tells me otherwise. May history judge me, my vote is not for, it's against." Cobos has said that the move defused tensions in the country between farmers and the state.