Broadnax's co-defendant, Anthony Torian, testified that Broadnax told him somebody needed to do something about the killing of Ahmad Lewis the day before.
Torian says he saw Broadnax enter an alley and then heard gunshots. Torian says Broadnax later told him that he killed two people.
Deputy District Attorney Mark Amador says the 19-year-old victims appeared to have nothing to do with Lewis' death.
Broadnax faces up to life in prison at his sentencing in February.
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