Kyle McClenagan/Houston Public Media
A Houston Police Department vehicle on July 9, 2026.
The Houston Police Department (HPD), in collaboration with the local FBI office, has identified and arrested a man allegedly connected to four cases of sexual assault that occurred in the city over three decades.
HPD, the FBI and Houston Mayor John Whitmire announced at a Friday news conference that Phillip Cerf, 62, had been arrested and charged with four counts of aggravated sexual assault. According to authorities, the assaults took place in north and northeast Houston between 1996 and 2016.
Luis Menendez-Sierra, HPD’s assistant chief of special investigations, said DNA collected in each of the four cases was used to allegedly connect Cerf to the assaults.
Sign up for the Hello, Houston! daily newsletter to get local reports like this delivered directly to your inbox.
“By comparing reports, forensic evidence, witness statements and investigative findings across multiple cases, detectives identified significant similarities that ultimately led to the identification of the suspect Phillip G. Cerf,” Menendez-Sierra said. “Since the charging of the suspect, we have already been contacted by [another] possible victim from 1988. Investigators are currently following up with that victim.”
Houston Mayor, Police Chief and FBI Announce Arrest of Sexual Assault Suspect https://t.co/DKkC2el4ai
— Houston Police (@houstonpolice) July 31, 2026
Cerf was arrested July 21 and was being held in the Harris County Jail after bond was denied, according to court records. Court records also show Cerf had previously been arrested in Harris County several times, but had never been charged with sexual assault.
FBI Special Agent in Charge Jason Hudson said DNA made available via genealogy services was used ahead of Cerf’s arrest.
“Our [Investigative Genetic Genealogy] IGG team use publicly accessible genealogy services to ID potential family members of the unknown suspect profile,” Hudson said. “Using information such as witness descriptions of the suspect, the location, and the timing of the crime, FBI personnel try to identify a likely suspect within the family tree. Only then do we seek a comparison between the potential suspect’s DNA and the DNA from the crime scene.”
Hudson claimed the use of genealogy services is not a violation of privacy.
“I want to be very, very clear,” he said. “The FBI is only able to see information that users have given genealogy services the permission to share with other customers. We cannot, and we do not violate privacy expectations or agreements.”
Menendez-Sierra said Cerf was a truck driver for approximately 16 years.
“The suspect may have driven trucks throughout the United States, so it is crucial that this information is disseminated so we may be able to find any other possible victims,” he said.
There are similarities in all four cases across the three-decade timeframe, according to Menendez-Sierra.
“All four cases appear to [have] occur[ed] during the late hours at night,” he said. “All four females were walking from one location to another. They were approached, provided, or given, offered a ride. At that point, once they got into the vehicle, they were taken to another location where they were sexually assaulted.”
Cerf’s court-appointed defense attorney did not immediately respond to a request for comment.
HPD is asking those with any information about additional potential assaults to call 713-308-1180.