 While in Congress, he taught at his alma mater's Law School, and was its Dean in 1920 and 1921.Elected on the UCR ticket, Melo broke with longtime UCR leader Hipólito Yrigoyen following the 1922 elections.Yrigoyen's fractious opposition, which together continued to enjoy a majority in the Upper House, appointed Melo Provisional President of the Senate in the same year.