USC grad student accused of drugging, raping victims over 4-year period

USC grad student named serial sex assault suspect

Sizhe "Steven" Weng, from, was named a serial sex assault suspect.

LOS ANGELES - Authorities are seeking additional victims of a man accused of a series of sexual assaults facilitated by drugs, according to the Los Angeles Police Department.

Sizhe Weng, a USC graduate student, faces eight felony counts, including rape and sodomy, with evidence suggesting a pattern of assaults dating back to 2021.

The backstory:

The investigation began in January 2025 after detectives with the LAPD's Robbery-Homicide Division received a tip from authorities in Germany, where Weng spent time. 

This led to a collaborative investigation with the FBI and German Federal Criminal Police, which resulted in a search and arrest warrant, officials said.

Sizhe Weng faces eight felony counts including rape and sodomy. / Los Angeles County Sheriff's Department.

On August 28, Weng — also known by first name Steven — was arrested for the alleged sexual assaults of three women after placing incapacitating drugs in their food and/or drinks between 2021 and 2024 while he was a doctoral student at USC, according to the Los Angeles County District Attorney's Office.

A search of his residence yielded evidence corroborating his involvement in multiple assaults, police said.

The DA's office filed eight felony counts against him on September 2.

What they're saying:

"No one should ever have to endure the trauma of being drugged, sexually assaulted and stripped of their ability to consent," District Attorney Nathan Hochman said in a statement announcing the charges. "Prosecutors in my office's Sex Crimes Division and our law enforcement partners will not rest until the defendant is held accountable for these horrific acts. We want every victim to know that their voices matter and we will fight to ensure you are heard."

USC issued the following statement in the wake of the investigations:

"Providing a safe environment for learning, teaching, and research is our top priority. The university has been fully cooperating with the Los Angeles Police Department in this matter. Although we cannot discuss individual cases due to student privacy laws, we can confirm that the university had already taken appropriate steps to bar the individual in question from campus pending resolution of the criminal proceedings. USC has not received any reports from individuals potentially impacted."

What's next:

Weng has pleaded not guilty and is due back in court on Jan 14. 

A date is scheduled to be set then for a hearing to determine whether there is sufficient evidence to allow the case to proceed to trial. 

He could face a potential life prison term and sex offender registration if convicted as charged, according to the DA's office. 

What you can do:

The LAPD has released this information to identify potential additional victims of Weng. 

Anyone who believes they may have been a victim is encouraged to contact the Robbery-Homicide Division at (213) 486-6890. 

During non-business hours or on weekends, calls can be made to 1-877-LAPD-24-7 (877-527-3247). 

For those who wish to remain anonymous, tips can be submitted to the LA Regional Crime Stoppers at 800-222-TIPS (800-222-8477), through their website, or via the "P3 Tips" mobile app.