The testimony by San Diego police Detective Deanna Warwick came on the first day of a preliminary hearing for 17-year-old Daniel Padilla, who is charged as an adult with murder and attempted murder for the death last Sept. 17 of Rochelle Quintana and the wounding of Sara Chavez.
Warwick said the surviving teen told her that she arrived by bus at the transit center with her pregnant sister and Quintana, and heard Padilla say something about her sibling.
"She said, `Why do you have to say that to my sister?' and punched him," Warwick testified.
Chavez told her that Quintana then asked Padilla where he was from, and he gave a gang neighborhood, according to Warwick. Quintana gave the name of a rival gang area, and the three began exchanging punches, the detective said.
Chavez said she "felt something on her side, and looked over and saw Rochelle on the ground and that she was bleeding," Warwick said.
The detective said another witness was heard asking Padilla why he had to pull out a knife.
Padilla is not a documented gang member, but Warwick said she was told by witnesses that he liked to claim his "area" and throw out gang signs. The detective said Chavez and Quintana both belonged to gangs.
The defendant got on a trolley after the stabbing, but was arrested before it left the station, Warwick said. The knife was found on a trolley car by a security guard, she said.
Quintana died at a hospital of a chest wound about an hour after the stabbing.
At the conclusion of the hearing, Judge Michael Wellington will decide if there is enough evidence to order Padilla to stand trial.
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