[1][2] The Río Piedras massacre of four Puerto Rican Nationalist Party members occurred on October 24, 1935.
The Nationalist Party blamed these deaths on Elisha Francis Riggs, a former United States Army Colonel whom, at the time, was the top U.S.-appointed police officer on the entire island.
Consequently, on February 23, 1936, Colonel Riggs was assassinated by Nationalists Hiram Rosado and Elías Beauchamp.
This prompted U.S Senator Millard Tydings to introduce a legislation to grant independence to Puerto Rico.
However Luis Muñoz Marín objected because, in his view, Puerto Rico was incapable of independence without U.S. economic support.
[3] In 1938, Dávila Monsanto joined various former members of the Liberal Party, such as Luis Muñoz Marín, Felisa Rincon de Gautier and Ernesto Ramos Antonini[3] and founded the "Partido Popular Democratico de Puerto Rico" known in English as the "Popular Democratic Party of Puerto Rico" (PDP).