The U.S. wants Wright returned to serve the rest of his 15- to 30-year jail sentence for a 1962 killing in New Jersey. Wright was captured in Portugal in September after a fingerprint provided by U.S. authorities was matched to his in a national Portuguese database.
Wright's lawyer, Manuel Luis Ferreira, told The Associated Press that the judge accepted his arguments that Wright is now Portuguese and that the statute of limitations on the killing had expired.
Authorities say Wright and three associates had already committed multiple armed robberies on Nov. 23, 1962, when Walter Patterson, a decorated World War II veteran and father of two, was shot dead in his gas station in Wall, New Jersey.
Wright spent seven years in the Bayside Sate Prison in New Jersey for the murder, before escaping in 1970.
He made his way to Detroit and became a militant in the Black Liberation Army. In 1972, Wright dressed as a priest and used an alias to hijack a Delta flight from Detroit to Miami along four others, police say.
After releasing the plane's 86 passengers for $1 million, the hijackers forced the plane to fly to Boston, then to Algeria, where the hijackers sought asylum.
Algeria gave the money and plane back to the U.S., and Wright and his comrades went underground in Europe. The other four were captured and convicted of hijacking in Paris, but Wright managed to avoid the dragnet and slipped away.
He got Portuguese citizenship through his 1991 marriage to a Portuguese woman and after the tiny West African nation Guinea-Bissau, a former Portuguese colony, gave him the new name of "Jose Luis Jorge dos Santos" complete with fake names for parents and made him a citizen.
Wright was captured in the seaside village where he has lived since 1993 less than an hour's drive from Lisbon, and was jailed for about two weeks. But a judge released him about a month ago under house arrest.
U.S. officials were "extremely disappointed" with the denial for extradition and "will review the decision and consult with Portuguese authorities to determine a path forward that results in Mr. Wright's return to the United States," according to a statement from the U.S. Embassy in Lisbon. The case could be appealed to a higher Portuguese court.
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