He was the federal interventor in the state of São Paulo nominated by Brazilian dictator Getúlio Vargas, serving between 1938 and 1941.

Known to be a populist, he built a strong electoral machine, the Social Progressive Party (PSP), which dominated state politics until 1964.

He was accused of being corrupt, but he was responsible for advances in social legislation and infrastructure: his candid supporters said "rouba mas faz" (he steals but he gets things done).

In 1964 he supported the president João Goulart's downfall, but in 1966 he fell from the military's favor.

His nephew, Reynaldo de Barros, was also mayor of São Paulo.