REDWOOD CITY, Calif. (KGO) -- It may have been the moment Tiffany Li first realized that the life she knew of wealth, privilege, and power was about to drastically change.
Li, 34, and her boyfriend Kaveh Bayat, 33, are on trial for murder. Prosecutors say she lured Keith Green, 27, the father of her two children, to her mansion in Hillsborough on April 28, 2016, where he was shot by Bayat.
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Defense attorneys maintain that Olivier Adella killed Green in a botched kidnapping. Adella was friends with the couple and had worked as Bayat's personal trainer and bodyguard.
The moment that would change everything for Li literally played out last week in a Redwood City courthouse when prosecutors played a video of a conversation she had with police.
With one sentence from San Mateo County Sheriff Detective Gaby Chaghouri, it would become very obvious to her that she was a suspect in the killing of Green.
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The date was Wednesday, May 4, 2016, the time 1:55 p.m. Green had been missing for nearly a week. The place was the San Mateo Sheriff substation in Millbrae. Li was there to talk to two detectives who were involved in the search for Green.
The detectives thanked her for coming in. They said they were alerted after she sent an email to the Hillsborough Police Department asking for advice in finding Green.
She wrote that she at first thought Green was pulling a scam or took off on his own, but now she believed he might be the victim of foul play. She asked if the department could refer her to a billboard company so she could enlist the public's help to find him.
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The detectives artfully got her to repeat her story in minute detail about meeting Green in the Millbrae Pancake House on the evening he disappeared.
She said she was there to discuss child custody. They met between 9:15 p.m. to "10-10:15ish," she said.
Li told the detectives that Green said he still loved her and wanted to be with her. She said that after the meeting she left him in the parking lot and drove away.
Detective Chaghouri then told her that they used tracking to precisely note the location of Green's phone.
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Next, Chaghouri uttered the sentence that would change everything:
"So what we did find out is that the phone went with you."
The exchange continued:
Li: "With me?"
Chaghouri: "With you."
Chaghouri: "And then it ends up at your house."
Li: "At my house? Okay. Like you mean together with me?"
Chaghouri: "To your house and then it travels with you from your house to 1800 Trousdale to Vu's house." (The detective was referring to Vu Ho, a friend and tenant at a condo in Burlingame that Li's family owned. Li said she stopped by to pick up a rent check from Ho on the night Green disappeared. Prosecutors say that was a sham alabi.)
Li: "Yeah, because I went to Vu's house right after."
Chaghouri: "Okay. And the phone is with you the entire time, Can you... "
Li: "As I explained, I have... I really have no idea. I don't want you guys to be pointing fingers because... "
Chaghouri: "It's a huge problem in that they match."
Chaghouri: "Because like you to just told us it's very accurate in pinpointing."
Chaghouri was referring to Li saying earlier in their conversation how accurate she knew phone tracking was because she used it to track down where Keith Green was when he was cheating on her.
Later in the exchange the detective asked her directly, "Would you harm him?"
Li: "No, I would not harm him. No, I would not. Just I don't want to bring my kids..."
Chaghouri: "I have to ask these questions. They're very hard questions. So would you harm Keith?"
Li: "No I would not harm Keith."
Chaghouri asked her if she knew of anyone who might want to harm Green and Li responded with the names of several people whom she suspected.
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Chaghouri showed Li search warrants to seize her phone and search her home.
The defense began presenting its witnesses just after the prosecution concluded its case on Thursday afternoon.
After four days off, the trial will resume on Tuesday, Oct. 15.
Defense attorneys will have an opportunity to lay out their case that Green's murder was the result of a kidnapping orchestrated by Adella.
Adella was going to be the prosecution's star witness. He planned to tell jurors that Li and Bayat offered him $50,000 to kill Green, but he refused.
Adella told police and ABC 7 News I-Team Reporter Dan Noyes that on the night Green went missing, the couple showed up in the garage of the Burlingame condo complex where he rented an apartment that was owned bly Li's family.
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Green's dead body was on the passenger seat of the car, Adella said. Li was driving and Bayat was in the backseat holding onto Green's body.
He says Bayat told him to dispose of the body - and that he went along because he felt threatened for life and the safety of his family.
He also said he was afraid the couple would try to pin the homicide on him. He drove north to Sonoma County and dumped Green's body in a remote location near Healdsburg.
Adella was sent back to jail last month and the prosecution decided to no longer use him as a witness after he contacted a defense witness, his former girlfriend, through Instagram.
His lawyer said the contact was wrong but he wasn't threatening. He had just suggested she contact the prosecutors' office and encouraged her to be more balanced in her view of the homicide, the attorney said.
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Defense attorneys countered that the witness did feel threatened. Prosecutors say they will take up Adella's case after the Li and Bayat trial is over.
In cross examination of the prosecution witnesses, defense attorneys went out of their way to impress on jurors that Adella is in jail facing the same charges as Li and Bayat.
Adella had said on the night Green went missing that at Li's request, he watched from a distance as Green and Li talked in her car the pancake house parking lot. He said he followed them for a time after they left before returning to his home in Burlingame.
But defense lawyers say that Adella "stalked" Li and noted how closely he followed Li in his car after she left the pancake house, implying that Green was in his car with him rather than with Li. Prosecutors say that Green's cell phone hooked into the WiFi in Li's house on the night he disappeared but defense lawyers say the phone could have hooked into the WiFi just being close to the property.
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Defense lawyers will take their turn this week laying out evidence suggesting that Adella, working with other individuals, were involved in a kidnapping plot targeting Green.
Defense attorneys also note that police found an expensive watch with Green's DNA in Adella's home.
Adella's wife, Uta Bredenstein, said they found the watch in a kitchen drawer when they moved into an apartment that was owned by Li's family.
The defense also noted that the emergency release inside Adella's trunk was disabled and that they believe that Adella put Green in his trunk and that Green fought to get out.
The defense also disputed that Li was emotionless when police first informed her that Green was found dead. On cross-examination with Li attorney Geoff Carr, San Mateo County Sheriff Sgt. John Carroll agreed that Li's voice changed from a "sing-song tone" to a more somber one after getting the news.
Carr also noted that when Carroll informed her of Green's death he said that he could not go into details because of the safety of the investigation.
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Carr rhetorically asked Carroll, "So do you think she may have listened to you?" suggesting there was nothing suspicious about her not asking about how Green died.
Defense attorneys say that Li and Bayat had no motive to kill Green and that Li had worked out a custody agreement with Green ten days before he disappeared.
But the prosecution says Li and Bayat were angry after Green made financial demands. Prosecutors showed jurors a text from Li to Bayat and which she used the term "green light," which they allege put the plans in action for them to kill Green. But defense attorneys say green light meant to go head with child custody plans that included a scheduled visitation the weekend after he disappeared.
As the police interrogation video of Li was played in court last week, Li , Bayat, and the jurors were looking down at a transcript of the interview. The audio quality was poor and nearly impossible to completely understand without the transcript.
But Li undoubtedly didn't need a transcript to recall those words from Chaghouri. That would change everything. A jury of twelve will decide later this month if that change will be forever.
Take a look at the latest stories and videos about the investigation into the death of Millbrae father Keith Green.
Hillsborough heiress murder trial update: Video of detectives confronting Tiffany Li with evidence shown to jurors