Roberto Rizo

Roberto Rizo was 17 years old when he died on Monday, Feb. 18, 2013, a day after he was stabbed at a house party in Van Nuys, in the San Fernando Valley. According to the Los Angeles County Medical Examiner-Coroner, he died of stab wounds suffered at 15740 W. Sherman Way. His death was ruled a homicide, and it is listed as a Los Angeles Police Department West Valley Division case.

Roberto was a student at Canoga Park High School. His sister-in-law told CBS Los Angeles that he was "an avid sports fan and a doting uncle who had plans to join the Marines after high school." "He was a great kid. He didn't deserve " she said.

The party was held at a home in the 15700 block of Sherman Way, near Haskell Avenue, in an area some reports called Lake Balboa. A resident of the house told CBS that his roommate had met a girl who invited hundreds of strangers to the backyard gathering, and ABC7 reported that about 150 people were there. Early on Sunday, Feb. 17, police said, a fight broke out and a group of assailants confronted Roberto, and one of them stabbed him multiple times in the upper body. He underwent emergency surgery but died the next day. Detectives said they did not believe the stabbing was gang-related.

In May 2013, West Valley detectives held a news conference with members of the Rizo family and released composite sketches of two men, described as Latinos in their mid-20s, who may have been involved. Detective John Dunlop said Roberto had been caught up in a confrontation between his group of friends and another group over the sale of nitrous oxide. A police notice announcing the news conference gave his age as 16. His family was convinced that someone at the crowded party had seen the attack or taken pictures. "You're out there, and you're taking pictures like crazy, you know, you're young and you're taking pictures. Someone saw something," his cousin, Gabriela Sandoval, told ABC7. "Please, from the bottom of our heart, put yourselves in our shoes and help us out here," she said.

Sherman Way is one of the main east-west boulevards of the San Fernando Valley, running past apartment buildings, strip malls and single-family streets. The surrounding part of the Valley includes Van Nuys Airport and the Sepulveda Basin, home to the Lake Balboa park and its lake, and the neighborhood is a mix of working families, renters and longtime homeowners.

By the mid-2010s Los Angeles was recording roughly 250 to 300 homicides a year, among the lowest totals in decades, yet many of those killings still went unsolved.

No arrest, criminal charge or court case connected to the death of Roberto Rizo could be found in news archives or public records. More than 12 years later, there is no public sign that anyone has been held responsible. Anyone who was at the party on Sherman Way near Haskell Avenue on the night of Feb. 16 and 17, 2013, who took photos or video there, or who recognizes the two men in the police sketches, may hold information that could help detectives. Detectives asked callers to reach West Valley homicide detectives at 374-7720. Even a small detail, such as a name overheard, a vehicle seen nearby or a conversation remembered, can help detectives move a case forward. Anyone with information can call the Los Angeles Police Department at 877-527-3247 or leave an anonymous tip with Crime Stoppers at 800-222-TIPS.