A Hays County judge sentenced 21-year-old Isaac Arispe to 40 years in prison on Aug. 24 for the 2020 murder of Christopher Trevino, a 19-year-old Texas A&M University-San Antonio student who was fatally shot while running to protect his younger sister during a drug robbery outside their Kyle home. Arispe was 15 years old at the time of the killing and was certified to stand trial as an adult, according to the Hays County District Attorney's Office.
According to KXAN Austin, a jury found Arispe guilty of murder in March, and he then chose to have State District Judge Sherri Tibbe determine his punishment rather than let the jury decide, a procedural split detailed by KVUE. Per the Hays County DA's account relayed in KXAN's reporting, Arispe had arranged to buy drugs from Trevino's younger sister, planned to rob whoever showed up, and pointed a gun at her before Trevino ran over to help. Prosecutors say Arispe then shot Trevino in the chest.
What Happened That Night in Kyle
Kyle Police Department officers responded to the 100 block of Dusky Thrush Drive at 1:50 a.m. on Dec. 19, 2020, and arrested the 15-year-old Arispe a short time later at a nearby apartment complex, according to KVUE's account of the initial police response. The Hays Free Press reports Trevino, a Hays High School graduate known affectionately as “Binkie,” had just returned home moments before the robbery attempt unfolded across the street. Texas A&M University-San Antonio, where Trevino was enrolled, held a memorial news conference in April 2021 to honor him, as reported by FOX 7 Austin.
Arispe's case moved from juvenile court to a capital murder charge in June 2022. While out on bond, he racked up additional charges, leading to a September 2023 arrest for family violence assault and bond violations, the Hays Free Press notes. Public court filings reviewed by Texas Defense Lawyer show Arispe also faced separate adult charges in Hays County courts in June and July 2023, including engaging in organized criminal activity and assault causing bodily injury to a family member, in cases numbered PREFCR-23-2515-D and 23-1878CR-1.
A Constitutional Fight Over Juvenile Sentencing
Before trial, Arispe's legal team filed a motion seeking to quash the capital murder charge, arguing that a de facto life sentence with 40-year parole eligibility for an offense committed at age 15 would violate the Eighth Amendment's prohibition on cruel and unusual punishment, per the Hays Free Press. Under Texas Family Code § 54.02, juvenile court judges may transfer jurisdiction over minors 14 or older to adult criminal court for serious felonies, but only after a mandatory diagnostic evaluation weighing community safety, offense severity, maturity, and criminal history, according to the Texas Constitution and Statutes.
Because Arispe was a juvenile at the time of the offense, U.S. Supreme Court precedent bars both the death penalty and mandatory life without parole in his case, capping his maximum punishment at life imprisonment with parole eligibility after 40 calendar years, the Hays Free Press explains. The 40-year sentence Judge Tibbe ultimately imposed sits at that constitutional ceiling.
Jail Infractions Weighed at Sentencing
Ahead of the August sentencing hearing, prosecutors filed a June 2025 Notice of Intent detailing Arispe's history of uncharged misconduct, including disposing of evidence on the day of the murder, transferring a substance that caused a school overdose, middle school assaults, street gang membership, and disobeying jail staff, according to KVUE. The Hays County DA's office said Arispe was involved in more than 30 documented incidents during his roughly three years in custody, per KXAN's reporting, including assaulting other inmates, possessing dangerous contraband, and messaging friends and family asking for bullets.
Corrections officers and staff provided evidence about those incidents, the Hays County DA's office said, and Judge Tibbe reviewed that record before issuing her sentence. Arispe received jail credit of 1,157 days toward his 40-year term. He was 21 years old at sentencing, nearly six years after the night he was arrested as a 15-year-old outside the Dusky Thrush Drive apartment complex where Trevino died trying to protect his sister.
