Antoinette Briley, 41, of Michigan was charged Friday night with two counts of first-degree murder for the deaths of her newborn twin sons in unincorporated Stickney Township.
On June 6, 2003, the victims were discovered by a Waste Management employee who was emptying trash bins in an alley in the 4800-block of South Latrobe Avenue, according to a Cook County sheriff's release.
The employee saw the bodies in the front lift bucket of her garbage truck, police said.
An autopsy determined the babies were born alive and died of asphyxiation, the release said.
"It was indescribable that someone would do that," said Stickney Township resident Dawn Pecnick.
Cook County sheriff's police said they conducted a thorough investigation at the time, but the case remained unsolved.
In 2018, they reopened the case and utilized DNA from evidence recovered from the scene in an effort to identify the birth mother using the latest developments in genetic genealogy, according to the release.
A breakthrough from that research and subsequent investigations allowed detectives to eventually identify Briley as the victims' potential birth mother, police said.
The technology is the same used that broke the case of the Golden State Killer, according to lead detective Ginny Georgantas.
"The sheriff's detectives and sheriff's police officers worked hard on this case then, it was never gone, it never was passed us," said the sheriff's Chief of Public Safety. "The things that they did back then, helped us today."
Detectives traveled to Holland, Michigan and obtained a discarded item containing Briley's DNA, which was matched to the DNA from the victims, police said.
"As part of the investigation, sheriff's police detectives traveled to Holland, Michigan, and obtained discarded items Briley's DNA, which was then matched to the DNA from the victims," Chief of Public Safety Leo Schmitz with the Cook County Sheriff's Office said in a press conference Saturday.
On Thursday, police said they obtained information that Briley was in Cook County and took her into custody after a traffic stop in Oak Lawn.
"Briley was transported to the sheriff's police headquarters here in Maywood, where she admitted post Miranda to her involvement in the birth, death, and disposal of the two deceased infants," Schmitz said.
Investigators say Briley lived about a mile and a half away from the crime scene. Pecnick remembers detectives questioning her and others in the neighborhood.
"I was in tears," she said. "I didn't, I couldn't; I was in shock."
"We did multiple interviews up and down the block, checking, doing canvases but we didn't get anything back then. That's why this case now jumping that way is so good," Schmitz added. "The murder happened 17 years ago, we don't ever give up."
Pecnick said she has always thought about the twins and what happened to them.
"What was going through her mind," Pecnick asked herself. "I think of them a lot."
Cook County Sheriff's Police said they and other agencies have been using genetic genealogy to review other cold cases.
"I'm happy that there's closure for the twins, there was no one fighting for them," said Georgantas.
Briley appeared in court for a bond hearing Saturday, which was set at $150,000, according to the Cook County Sheriff's Office.