The judge's mistrial declaration today means 39-year-old Johnathan Doody will face another retrial.
The retrial that ended today began Aug. 12 because an appeals court had overturned his previous conviction. The jury had deliberated for about seven days when they informed the judge yesterday they had reached an impasse.
Doody originally was convicted in 1993 and sentenced to 281 years in prison.
Another man, Allesandro "Alex" Garcia, pleaded guilty in the killings and was sentenced to life in prison in exchange for his testimony against Doody and a promise that prosecutors wouldn't seek the death penalty.
Each victim was shot in the back of the head.
Doody faced 20 counts, including robbery and burglary and nine charges of first-degree murder. Prosecutors have already indicated they plan to put Doody on trial again.
During the retrial, Doody's attorney urged jurors to discount Garcia's testimony, saying he was a "sophisticated and savvy" teenager at the time who lied to minimize his involvement.
The 9th US Circuit Court of Appeals overturned Doody's conviction and ruled his confession inadmissible partly because he wasn't properly read his rights.
In the confession, Doody said he went to the temple during the robbery but claimed he was outside when the shootings occurred.
The appeals court's decision meant prosecutors couldn't use Doody's confession at his retrial. They instead relied largely on Garcia's testimony.
