Following the Río Piedras massacre in 1935 , US Senator Millard Tydings in 1936 introduced a bill in Congress for Puerto Rican independence . The Puerto Rican parties supported the bill , but Muñoz Marín opposed it , saying it had unfavorable economic aspects . Tydings did not gain passage of the bill
Río Piedras massacre
Río Piedras massacre
Antonio Rafael Barceló