<P> During the latter years of the Roosevelt--Truman administrations, the internal governance was changed in a compromise reached with Luis Muñoz Marín and other Puerto Rican leaders . In 1946, President Truman appointed the first Puerto Rican - born governor, Jesús T. Piñero . </P> <P> Since 2007, the Puerto Rico State Department has developed a protocol to issue certificates of Puerto Rican citizenship to Puerto Ricans . In order to be eligible, applicants must have been born in Puerto Rico; born outside of Puerto Rico to a Puerto Rican--born parent; or be an American citizen with at least one year of residence in Puerto Rico . </P> <P> In 1947, the U.S. granted Puerto Ricans the right to democratically elect their own governor . In 1948, Luis Muñoz Marín became the first popularly elected governor of Puerto Rico . </P> <P> A bill was introduced before the Puerto Rican Senate which would restrain the rights of the independence and nationalist movements in the island . The Senate at the time was controlled by the Popular Democratic Party (PPD), and was presided over by Luis Muñoz Marín . The bill, also known as the Gag Law (Spanish: Ley de la Mordaza), was approved by the legislature on May 21, 1948 . It made it illegal to display a Puerto Rican flag, to sing a pro-independence tune, to talk of independence, or to campaign for independence . </P>

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