 He became active in the youth wing of the Peronist Justicialist Party, and by 1987 he had a key role in the administration of Trelew's municipality, under Néstor Perl.Das Neves was candidate for Mayor of Trelew in 1991 and won the first round, but lost in the second.The following year he became leader of the Chubut Justicialist Party and was elected to the Argentine Chamber of Deputies for Chubut in 1995.