30-year-old Chinese national and USC PhD student Weng Sijie has been arrested on suspicion of drugging and sexually assaulting three women, facing eight criminal charges. According to the court indictment, Weng committed the crimes by tying up the victims, injecting sedatives into their anuses, and taking nude photographs. All three victims were friends of his, and one had even known him since childhood. According to the Los Angeles Times, he initially confessed his crimes to the LAPD but later pleaded not guilty.
According to Weng Sijie’s LinkedIn profile, Weng began pursuing his PhD in Electrical Engineering at the University of Southern California in August 2020 and started working as a teaching assistant in 2023. Weng was arrested on August 28 of this year, suspected of repeatedly drugging and sexually assaulting three women between 2021 and 2024. The Los Angeles County District Attorney’s Office states that Weng has been charged with rape, sodomy using controlled substances or narcotics, rape using controlled substances, and sexual assault using controlled substances or narcotics. He has denied all the charges.
He is alleged to have purchased the drugs from a Chinese national in Germany, to make women lose consciousness. The drugs include midazolam, benzodiazepines, and sevoflurane.
All Victims Were Friends and Classmates
Case details reveal that the first victim, Jane Doe 1 (alias), was Weng Sijie’s childhood friend. In December 2021, the two traveled to San Diego together. Weng had earlier ground the drugs into powder, dissolved them in water, and put them in a small bottle. He also brought leather ropes and dental instruments. While drinking at a bar, he spiked her drink with the sedative when she was not looking.
After returning to the hotel, Weng used a syringe and test tube to inject the drug into the victim’s rectum. He also used a towel soaked in the sedative to cover her mouth and nose to keep her unconscious. During the assault, Weng tied her up with leather ropes; the victim struggled and kicked but Weng continued the assault.
Weng also posed the victim in submissive positions and took nude photos and videos. In one photo, the unconscious Jane Doe 1 had a dental device in her mouth, exposing her teeth and gums; in another, her thighs were bound with leather ropes, exposing her private parts.
The second victim, Jane Doe 2 (alias), was a Chinese student who had just arrived in the US and was Weng Sijie's friend. On her very first day in the US, Weng sexually assaulted her. According to case details, in August 2022, Weng picked up Jane Doe 2 from the airport and spiked her airport-bought drink with the sedative. After arriving at her Airbnb and falling asleep, Weng assaulted her with the same methods he used on the previous victim and took nude photos.
The third victim, Jane Doe 3 (alias), was Weng’s PhD classmate and friend. Between 2023 and 2024, he sexually assaulted her three times at her residence. The first time was in 2023, when Weng put two powdered sedative pills in her food. After she fell asleep, Weng touched her all over, including her chest and private parts. The following two assaults left Jane Doe 3 so dizzy after waking up that she had to seek medical attention.
Police Find Album of Nude Photos at Residence
After Weng Sijie’s arrest, investigators searched his residence and found a photo album filled with nude photos he had taken of the three victims.
Investigators also found several small bottles containing drugs. While some of the drugs have yet to be completely tested, one bottle was found to contain midazolam. Police also discovered surveillance and pinhole cameras, as well as an SD memory card containing more videos and photos of the victims.
During police interrogation, Weng initially admitted to drugging and sexually assaulting the three victims, providing details of his crimes, but has since pleaded not guilty.