Martinez was killed by a man dressed in black and holding an umbrella, according to police at the time.
The gunman was never caught, leaving her son, Alexander Angulo, to navigate major milestones, including college graduation, without answers.
"It was like a little rough, a little hard. Knowing all these years like not hearing anything about like any updates on the case. But me and the family we just put it in the hands of God and thankfully, you know, something came up," Angulo said.
A private investigator now says he has provided police with a critical new lead. Manuel Gomez said he received a call from the mother of the alleged killer.
"The mother of the killer called me. She was on the phone crying and talking to me and telling me that her son was the murderer of Wendy Martinez," Gomez said.
Gomez recorded the mother recounting her son's confession. After learning of the new information, a detective contacted Angulo, telling him police had reached out to the lab "to see if the possible perpetrator's DNA that is on file is able to be tested against the umbrella handle that was on scene."
"Getting like this clue out of nowhere was just like... I didn't know how to react. It was just shocking," Angulo said.
At the time of the shooting, police suspected the gunman had been targeting one of Martinez's other sons in an act of gang retaliation. That son was not home, and Martinez was killed after answering the door.
Angulo said he continues striving to honor his mother's hopes for him.
"I just want to be successful for my mom. She was a hardworking lady. All she wanted was the best for me. I'm just trying to grant all the wishes she had," he said.
One of those wishes, he added, is justice. He hopes the new evidence will lead to an arrest in his mother's killing.
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