Lawrence Ballesteros was stabbed to death in Sept. 2012, just days after a U.S. Marshals sweep outed him as a registered sex offender.
Ballesteros hid the fact that he was a registered sex offender from his neighbors and landlords in Southwest Fresno. But when a sex offender sweep gave him away, he disappeared for a couple weeks. The day he came back, he turned up dead.
A trail of evidence led police from an Army Reserve center to the alleyway behind a Southwest Fresno shopping center, and then to a home.
"They confronted him and they murdered him right there," prosecutor Jeff Dupras said.
Dupras says David Barrera and Patricia Perez killed Ballesteros. He says evidence proves the murder was a two-person job.
"We know this because he had these marks on his neck," Dupras said. "While one of them was doing this, the other person stabbed him 58 times."
Ballesteros was a convicted rapist who hid his past from many of those around him, including Perez, who rented him a detached garage.
But when U.S. Marshals conducted a sweep to make sure sex offenders were where they were supposed to be, Ballesteros couldn't hide it any more.
With her girlfriend's two teenagers in her home, prosecutors say Perez mistakenly believed he was a pedophile, giving her a motive to kill. Her attorney disagrees.
"The only youngsters that Patricia Perez has that are close to her are her grandchildren and none of them live there," said Mark Siegel.
Surveillance video from the Army Reserve center on the night of the murder shows a pickup truck arriving a few feet from the gate, where the body was found.
Police later found Ballesteros' blood in Barrera's pickup. But his attorney says there's nothing proving Barrera committed murder.
"Maybe he wasn't even involved in the murder but let somebody use his truck," said defense attorney Gerald Schwab. "Or even say for example he was driving the truck, that doesn't put him with a murder weapon in his hand killing anybody."
A teenage girl living in Perez's home could be a key witness in a two-week trial. Prosecutors say she saw Perez and Barrera by his truck the night of the murder just before the time the body was dumped.