text: On March 21, 1937, the Nationalist Party organized a peaceful march in the southern city of Ponce. At the last moment, the permit was withdrawn, and the Insular Police (a force "somewhat resembling the National Guard of the typical U.S. state" and which answered to the U.S.-appointed governor Blanton Winship) were arrayed against the marchers. They opened fire upon what a U.S. Congressman and others reported were unarmed and defenseless Cadets and bystanders alike, killing 19 and badly wounding over 200 more.
  Many of these unarmed people were shot in the back while trying to run away – including a 7-year old girl, who died as a result. An ACLU report declared it a massacre and it has since been known as the Ponce massacre. The march had been organized to commemorate the ending of slavery in Puerto Rico by the governing Spanish National Assembly in 1873, and to protest the incarceration by the U.S. government of nationalist leader Pedro Albizu Campos. Soon thereafter, the Puerto Rican government arrested the leadership of the Nationalist party, including Pedro Albizu Campos. In two trials, they were convicted of conspiracy to overthrow the government of the United States.
  A government investigation into the incident drew few conclusions. A second, independent investigation ordered by the US Commission for Civil Rights (May 5, 1937) led by Arthur Garfield Hays (a member of the ACLU) with Fulgencio Piñero, Emilio Belaval, Jose Davila Rice, Antonio Ayuyo Valdivieso, Manuel Diaz Garcia, and Franscisco M. Zeno, concluded that the events on March 21constituted a massacre. The report harshly criticized the repressive tactics and massive civil rights violations by the administration of Governor Blanton Winship.