The 15-year-old had claimed she was forced Friday night into a car with four males at gunpoint and driven around for several hours before two of them raped her.
But the girl called Richmond police around 1 p.m. Sunday and told them the story was not true, said Lt. Mark Gagan.
The girl told police Sunday that she had had consensual sex with someone, but needed an explanation for why she was late getting home Friday night, Gagan said.
The girl's accusations prompted a major police investigation in Richmond, where the gang rape of a high school girl outside a homecoming dance made national headlines in October.
in October and November and a healing rally and candlelight vigil for the victim was held Nov. 3, 2009 at the school where the crime was alleged to have taken place.
Dozens of patrol officers, detectives, forensic technicians and nurses had been working on the investigation since the 15-year-old flagged down a San Pablo police officer early Saturday and claimed she had been kidnapped and raped.
"We took her allegations very serious and spent a lot of time, energy and resources to investigate this," Gagan said.
On Sunday afternoon, police found evidence, including video footage, that confirmed the girl had made up her initial story, Gagan said.
Richmond police are trying to determine what happened Friday night and could pursue statutory rape charges if the person she had sex with is an adult, he said.
Investigators have not determined whether they will pursue charges against the girl for making the false report.
"We don't want to create a situation where people are hesitant to report sex crimes," Gagan said. "On the other hand, this 15-year-old girl knew she was completely fabricating her story and misleading us about what really happened."
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