The conspiracy suffered a setback in June with Luís Carlos Prestes. A former member of the "Tenentismo" movement, Prestes adopted the ideas of Karl Marx and began to support communism. After some time, this led to the failed attempt at a communist overthrow by the Liberal Alliance.Soon thereafter, another setback to the conspiracy occurred as Siqueira Campos died in a plane crash.
Smoot-Hawley Tariff Act passed, placing more stress on the weakening global economy, primarily through the collapse in trade of agricultural products, which strained banks that had lent heavily to farmers. Further decreases in trade of manufactured products led to layoffs and reduced corporate profits, weakening the economy. General consensus among economists is that the Smoot-Hawley Act did not cause the Depression, but did worsen it and stunted recovery efforts after 1933. Exports declined from $5.2 billion in 1929 to just $1.7 billion in 1933.