Secrets to what sparked Oakland police sex scandal revealed

OAKLAND, Calif. -- The ABC7 News I-Team has exclusive new information about the Oakland police sex scandal that has spread to six other departments. It all may have remained a secret, had an officer answered "a single phone call". Dan Noyes has interviewed the teenager at the center of this controversy and he joins us with the latest.

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The young woman showed me texts and photos of officers she had sex with. She says some paid, most did not. But, she felt she could get protection and information from them, as she worked the streets.

The 18-year-old who calls herself Celeste Guap tells me she had sex with more than 30 Bay Area police officers, sergeants and captains, four of them when she was underage, including Oakland Officer Brendan O'Brien.

Celeste says she met O'Brien last year as she ran away from a pimp on International Boulevard.

Celeste: "He started chasing me down the block."

Dan: "A pimp did."

Celeste: "And then Brendan came and saved me."

Texts Celeste shared with me show they were close. O'Brien wrote, "There's no women in my life." She answers, "I don't believe you." He responds, "Except for you. I'm serious."

Celeste: "We tell each other you're my only, you know, like that, but he knew what it was."

Dan: "What you're saying, at the same time you were seeing others, including other officers."

Celeste: "Yes, he knew I was seeing other officers, too."

Last August, Celeste went to Puerto Rico to celebrate her 18th birthday. On the last night she found herself alone in a rough area, drunk, in a bikini, the sun going down and her cellphone on the verge of dying. She called Brendan O'Brien for help, but he didn't pick up.

RELATED: Several Bay Area officers under investigation for possible involvement in sex scandal

She saw he was active on Facebook and thought he was ignoring her.

"Had I not been drinking that night, I wouldn't of said a lot of the things that I said," she said.

They argued by text, and she threatened to tell his superiors at the Oakland Police Department he had sex with her when she was 17. O'Brien did not take it well.

Dan: "That last conversation with you by text, he mentioned hurting himself, didn't he?"

Celeste: "He asked me, he asked me, asked me, 'How would you feel if I died?'"

Then, Celeste says she sent him a screenshot of a message to an OPD sergeant, in which she revealed their underage sex and named other officers she was involved with, as well.

Autopsy reports show Brendan O'Brien shot himself within hours, perhaps minutes, of that exchange with Celeste. The veteran was wearing his Marine Corps T-shirt at the time.

RELATED: SFPD looking at possible links to young victim in OPD sex scandal

In his suicide note, sources tell the I-Team that O'Brien cited the pressure of his wife's suicide in that same apartment the year before. He also said Celeste was blackmailing him.

Dan: "In his suicide note he said that he thought you were trying to blackmail him. Was that the case?"

Celeste: "No."

Also in the note, he said he never had sex with her.

Dan: "Is that true?"

Celeste: "No, it's not true."

O'Brien's suicide note sparked the investigation that has now spread to seven law enforcement agencies. At the center of it, all those texts and photos from Celeste Guap's cellphone.

"I didn't want none of this to come out or happen," she said. "I feel bad, I feel guilty because, I mean, it was adult consensual fun," she said.

But, if what Celeste says is true, several officers could be charged with statutory rape and others gave her information on undercover operations.

On Tuesday at 6 p.m., you'll learn about one OPD officer who had a tremendous, positive impact on her at a young age. But his death on the job sent her spiraling to a life of prostitution.

Click here for more stories and videos by Dan Noyes and the I-Team.