SANTIAGO, Chile — A Chilean judge on Monday decided not to charge the father of one presidential candidate with the torture and murder of her rival's father in 1974.

It's the second time in a year that Judge Mario Carroza has declined to charge Gen. Fernando Matthei for the torture that led to Gen. Alberto Bachelet's death.

Human rights groups said they would appeal the decision.

"We have enough precedents to appeal again," Alicia Lira, head of the Group of Families of the Politically Executed, told Radio Cooperativa.

Lira said Matthei has acknowledged that he visited the Air War Academy where Bachelet was tortured and met with some of the torturers.

But both families have said Matthei had no direct involvement in the death of Bachelet, who was convicted by dictator Augusto Pinochet's military of being a traitor for not joining the 1973 coup that ousted Marxist President Salvador Allende.

The retired general's daughter, Evelyn Matthei, is running as the center-right coalition's presidential candidate against the victim's daughter, former President Michelle Bachelet, who represents the center-left bloc.

The election is Nov. 17, and opinion polls give a big lead to Bachelet, who was president in 2006-10.

The two candidates were close in the 1960s. Their fathers served at the same military base and the girls were playmates at the same elementary school.

Allende put Gen. Bachelet in charge of overseeing food sales nationwide in 1972, as other high-ranking military officers were conspiring to end his presidency. Many products were in short supply as Allende's right-wing opponents, financed by the administration of U.S. President Richard Nixon, held back goods and instigated strikes to create a sense of chaos.

The elder Bachelet remained loyal to Allende to the end. He refused to endorse the Sept. 11, 1973, coup even after Allende committed suicide while making his last stand in the bombed-out La Moneda presidential palace. Bachelet was arrested the same day, convicted that December and survived in prison until March 12, 1974.

A forensic study found the general probably died of heart problems caused by torture at the academy.

Gen. Matthei was named head of the academy while he was still stationed in Britain. He returned to Chile shortly after the coup and became Pinochet's health minister and then a member of the junta.

"Accusing me of the death of my friend, Gen. Bachelet, is grotesque," he told CNN Chile recently.