Sean Angold, Lila Alligood and Morrison Haze Lampley were escorted back to the Bay area Monday after they were arrested in Portland last week for the murders of a yoga teacher and a woman backpacking thorough the Bay Area.
The suspects could face life in prison or the death penalty.
With shaved heads and wearing orange jumpsuits, Alligood, 18; Angold, 24; and Lampley, 23, arrived at the Marin County Jail.
Investigators say they killed 67-year-old hiker Steve Carter in Marin County and 23-year-old Canadian tourist Audrey Carey in Golden Gate Park. Carter's dog was also shot and injured.
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Several people reported seeing the trio on Haight Street in San Francisco around the time of Carey's death.
Escape from New York Pizza employee Jamie Pannozzo recalls serving someone who looked like Alligood.
"There was no violent interaction. There was no aggression," Pannozzo said.
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Public tips and security camera surveillance video helped investigators identify the suspects.
All three are facing murder, robbery, stolen vehicle and property, along with animal cruelty charges. Lampley is also facing stolen firearm and ex-felon in possession of a firearm charges.
They'll stand trial for both murders in Marin County, even though they took place in different counties.
ABC7 Legal Analyst Gil Soffer says it could be a strategic move.
"It's a little unusual but it happens," Soffer said. "If you're a prosecutor and you can introduce evidence about two murders in the same form it can strengthen your case against each one of them."
The special circumstances that make them eligible for the death penalty include multiple murders, lying in wait and murder during a robbery.
The arraignment hearings for all three are Wednesday at 9 a.m. in Marin County Superior Court.