A 52-year-old woman is in custody and has been charged with murder for allegedly killing her newborn boy and leaving him in a bag in Castro Valley more than 30 years ago, Alameda County sheriff's officials said Monday.
Lesa Lopez, a resident of Salida in Stanislaus County, was arrested for a case that began on May 15, 1988, when two youths discovered the lifeless body of a newborn baby inside a bag at the top of a creek embankment near Madison and Seaview avenues.
Investigators determined the boy was alive at birth and was the victim of a homicide, but despite outreach to hospitals and local media outlets in the days and weeks after the body was discovered, no arrest was made at the time, according to the sheriff's office.
In 2005, DNA evidence was identified from the crime scene by the sheriff's crime laboratory, with a female DNA profile entered in the national Combined DNA Index System.
In 2019, investigators reopened the case and used new investigative techniques like forensic genetic genealogy -- a process used in high-profile cases like the so-called Golden State Killer in 2018 -- to try to determine the suspect's identity.
This past June, the genealogy research, combined with DNA analysis of trash discarded by Lopez, allegedly led investigators to identify her as the prime suspect in the killing of the baby boy.
On July 23, investigators contacted her at her home and she said she hid the pregnancy from her family and friends and described what happened on May 15, 1988, sheriff's officials said.
She has been booked into Santa Rita Jail on $2 million bail and is set to return to court on Wednesday for a plea hearing on the murder charge filed by the Alameda County District Attorney's Office.
Although an arrest has been made, anyone who has information about the case is asked to call Detective Pat Smyth at 510-667-7538 or an anonymous tip line at 510-667-3622.