On April 8, 2020, investigators were called to The Arbors at East Cobb complex when another juvenile reported his girlfriend missing, Marietta police previously said.
“He stated he tried to find her but was unable and that she had been missing for approximately two hours before he called 911 for help,” police said.
The following day, the body of 14-year-old Janina Valenzuela, of Marietta, was found in the woods behind the apartments.
Prosecutors said Rivas threatened both Valenzuela and her boyfriend and the two ran, but Rivas caught up with the girl and killed her.
When he was arrested, Rivas denied he had killed the girl and said he saw someone else do it, according to investigators.
“In a subsequent letter obtained by law enforcement that the defendant mailed from jail, he confessed to killing the juvenile female and admitted his intention to also kill the male,” the DA’s office said.
Through searches of Rivas’ phone, social media and home, investigators determined he was associated with the MS-13 street gang. The knife used in the killing was found in the suspect’s home and GBI testing confirmed it contained the victim’s DNA, according to investigators.
Rivas’ sentence puts him in a unique cohort of defendants known as juvenile lifers: those under 18 sentenced to life without parole. Citing developmental differences between adults and children and the capacity for rehabilitation, the U.S. Supreme Court, in 2012, ruled that the sentence amounts to cruel and unusual punishment and should only used in rare cases.
Despite this ruling, an AJC investigation published in September found Georgia has seen a 100% increase in its number of juvenile lifers since the high court’s decision. The state accounts for more than a quarter of the nation’s new juvenile lifers during this period, with 81% being Black and largely poor.
Rivas is the 32nd young person to be sentenced to life without parole in Georgia since 2012.
“This outcome is tragic at every level,” said Melissa Carter, the executive director of the Barton Child Law and Policy Center at Emory University. “An innocent life was lost, and effectively doing the same for another by locking him up forever disregards what we know to be true about child development, what we believe about liberty, and the clear trend among states to ban juvenile life without parole.”