DNA evidence leads to arrest of woman for her baby’s 1988 killing

Lesa Lopez was arrested July 23 and charged with murder. She is being held on bail of $2 million.
(Alameda County Sheriff’s Office)

A California woman has been arrested in the death of her newborn boy 32 years ago in the Bay Area, in a case that was solved decades later because of genetic genealogy, authorities said Monday.

Lesa Lopez, 52, admitted to investigators that she was the mother of the baby and implicated herself in the killing, Alameda County Sheriff’s Office spokesman Sgt. Ray Kelly said in a statement.

“Lopez, who was 20 years old at the time ... told investigators she hid the pregnancy from her family and friends and provided details of what happened,” he said.


Lopez, of Salida in Stanislaus County, was arrested July 23 and charged with murder. She is being held on bail of $2 million. It wasn’t immediately known if she has an attorney who can speak on her behalf.

Two children playing found the baby’s body on May 15, 1988, inside a paper bag left among trees and bushes on the bank of a creek in Castro Valley. An autopsy revealed the baby was alive at birth and was killed, Kelly said.

The boy, identified by investigators as Baby Joe Doe, was given a funeral at St. Leander Church in San Leandro attended by more than 200 people. A priest posthumously named him Richard Jayson Terrance Rein after the church’s vicars and priests.

In 2005, the DNA of a woman was found in evidence collected from the crime scene. Investigators believed it belonged to the baby’s mother, who was considered a suspect, but she couldn’t be identified.

Multiple investigators with the sheriff’s office tried to solve the case over the last 32 years “for a baby boy who never had a voice and never had the chance of living a full life,” Kelly said.

Last year, investigators again took up the case with the help of experts in forensic genetic genealogy from the FBI and private labs, including Oklahoma-based DNA solutions and Gene By Gene, which owns the genealogy website FamilyTreeDNA.


After extensive genealogy research, surveillance and DNA collected from Lopez’s discarded trash, cold-case investigators linked Lopez to the crime scene, Kelly said.

They used the same advanced DNA testing that helped crack the decades-old Golden State Killer case. In 2018, police investigators identified Joseph DeAngelo Jr., a former police officer, after using DNA from crime scenes to find relatives of their suspect through a popular genealogy website database. They tailed DeAngelo and secretly collected DNA from his car door and a discarded tissue to get an arrest warrant. DeAngelo, who terrorized California as a serial burglar and rapist and went on to kill more than a dozen people while evading capture for decades, pleaded guilty last month.