Deportation proceedings were initiated against him in a federal court in Idaho, his opponents claiming that he was a foreign national illegally residing in the United States. During the trial, Robinson contended that although he had been raised in England, he had been born in New York City while his father was visiting the U.S., and was therefore a U.S. citizen. Nonetheless he was ordered to leave the country. Robinson traveled to Cuba, where he stayed briefly while Idaho Senator William Borah intervened on his behalf and helped him to obtain a visa. Robinson was soon back in Idaho and became a naturalized citizen of the United States in 1942.