“I just don’t think it would be good for the country,” said Ramón Jáuregui, a lawmaker with the opposition Socialist Party, who opposed Franco during the 1970s but is reluctant to break the amnesty pact. “We don’t know where it starts and where it finishes. If we take someone who was a torturer in 1970, why aren’t we going to go after some ministers in Franco’s government who are still alive? Why not the courts? Where do we set the limit?”

Spain’s government is already facing growing pressure from the United Nations. Pablo de Greiff, a United Nations special rapporteur, said Spain “lagged behind” other European countries in addressing its recent past. He said Spain’s government had done too little to help victims of the Franco era, and recommended setting aside the amnesty law so that prosecutions could go forward, either in Argentina or in Spain.

“Some problems do not go away,” Mr. de Greiff, the special rapporteur on the promotion of truth, justice, reparation and guarantees of non-recurrence, said in an interview. “They cannot be swept under the rug. People, not surprisingly, do not forget.”

Franco was a contemporary of Hitler and Mussolini, though his dictatorship lasted until the 1970s and his legacy is more complicated, and contested. Not far from Mr. Pacheco’s apartment, the National Francisco Franco Foundation serves as the watchdog of the Franco legacy. The small office is like a time capsule from the dictatorship: Portraits of Franco hang on the walls, while a small display offers souvenir Franco T-shirts and other memorabilia.

“Since the Catholic Kings, Franco was in power the longest, and with the most public support,” said Jaime Alonso, the foundation’s spokesman and second in command. “He had great popular support until his death — despite what the propagandists maintain.”

Mr. Alonso, a lawyer, argues that Franco was not a dictator and scoffs at evidence of forced labor and postwar atrocities. “What is happening now is the need the left has to delegitimize history,” Mr. Alonso said.