AP

Undated photo of convicted murderer Juan Corona.

SACRAMENTO, Calif. -- A California man who once was the nation's worst known serial killer is up for parole, four decades after the mutilated bodies of 25 farmworkers were unearthed in orchards north of Sacramento.

Juan Corona, 77, has been diagnosed with dementia and mental illness. He is making his seventh bid for parole from Corcoran State Prison in the southern Central Valley.

None of his victims' relatives were expected to attend Monday's hearing, which Sutter County District Attorney Carl Adams said is a sad testament to Corona's crime, which targeted people who had few relatives.

"We have had no contact with survivors for two decades now. The people who he killed were farm laborers who were itinerant. Most of them didn't have relatives who could be contacted back in the '70s at the time of trial," Adams said.

Four of the bodies have never been identified. The bodies of 14 of Corona's victims were never claimed by family members after they were discovered in 1971.

"Not even a single person has family here," Corona told a prison psychologist before his parole was last denied in 2003. "They were all ready to go to the next world."

Corona, a farm labor contractor with a history of mental illness, was convicted of stabbing the men, hacking open their heads and burying their remains near Yuba City, 40 miles north of Sacramento.

His attorney, Leon Harris III of Bakersfield, declined to comment before the hearing.

Assortment of weapons
His first conviction in 1973 was overturned on appeal, but he was convicted again in 1982 and sentenced to 25 concurrent life sentences. He was not eligible for the death penalty because California's capital punishment law had been ruled unconstitutional at the time.

It was the worst known killing spree in U.S. history, until John Wayne Gacy Jr. was convicted in 1980 of murdering 33 young men and boys in his Chicago home. Gacy was executed in 1994 in Illinois.

Investigators found a machete, a meat cleaver, a double-bladed ax and a wooden club, all stained with blood, in Corona's home, along with a ledger book containing the names of seven of the victims.

Most of his victims were white, though several were black or Native American. There was no known racial motivation for his crimes, Adams said.

Corona, a Mexican national and native of Jalisco, Mexico, has maintained his innocence, though at earlier parole hearings he acted confused and told the parole board he didn't recall much. His attorneys have argued that his mental and physical condition makes him less dangerous.

Adams said his deterioration makes him a greater threat to himself and others.

"He is unreliably dangerous. He's also old and not in a condition where he can do well on the streets without prison supervision," Adams said. "Releasing him into the public wouldn't be doing him any good or the public any good."

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