Third District Juvenile Court Judge David L. Johnson has presided over delinquency and related cases serving Salt Lake, Summit, and Tooele counties since his appointment by Gov. Spencer Cox in February 2022. He is scheduled to retire effective September 16, 2026. While juvenile court proceedings are often confidential and rarely produce published opinions, Johnson has drawn attention for his handling of at least two high-profile cases involving serious violent charges against minors.)
Johnson’s official biography notes that he earned a J.D. from McGeorge School of Law in 2006 and previously represented children for more than 14 years as a guardian ad litem and then as a delinquency defense attorney. He received the Excellence in Juvenile Representation award from Utah Juvenile Defender Attorneys in 2017. Before joining the bench, he served as an assistant attorney general and general counsel for the Utah Department of Human Services. He has presented nationally on juvenile human trafficking and served on boards addressing trafficking and juvenile homelessness.
The most extensively reported case under Johnson involves a teen identified publicly as Emiliano. On Aug. 17, 2023, then-14-year-old Emiliano stabbed and killed 24-year-old Niusami Auelua in Scottsdale Park in West Valley City. Emiliano maintained he acted in self-defense after Auelua, a probation fugitive with high levels of methamphetamine in his system, robbed him at gunpoint. The Salt Lake County District Attorney’s Office initially declined charges citing self-defense elements but later filed first-degree murder and related charges.
In 2024, Emiliano pleaded guilty to manslaughter under a plea agreement and was sentenced to secure care. In March 2025, after defense motions citing undisclosed evidence and an alleged inappropriate personal relationship between Deputy District Attorney Adrianna Davis (who charged the case) and West Valley City Police Detective Josue Llil (a lead investigator), Johnson vacated the plea and conviction. He later transferred the teen to a residential treatment facility.
In a 15-page May 2025 ruling, Johnson disqualified the entire Salt Lake County District Attorney’s Office—including District Attorney Sim Gill—from further participation, an action he and reporting described as unprecedented in Utah’s juvenile court system. Johnson cited failures to disclose the relationship, lack of transparency in internal investigations, discovery violations, and an overall appearance of impropriety that undermined due process and public confidence. He wrote that disqualification was necessary “to protect the minor’s due process rights and uphold public confidence in the justice system.” The Utah Attorney General’s Office took over as special prosecutor.
On Aug. 25, 2025, after the special prosecutor indicated he could not disprove the self-defense claim, Johnson dismissed the case against Emiliano with prejudice, barring refiling. The ruling cited self-defense and insufficient evidence. A subsequent federal civil rights lawsuit filed in 2026 by Emiliano’s mother seeking at least $20 million alleges malicious prosecution against the DA’s office, West Valley police, and individuals involved.
Earlier in his tenure, Johnson handled proceedings in the January 2022 shooting near Hunter High School in West Valley City that killed two students, Paul Tahi, 15, and Tivani Lopati, 14, and seriously wounded a third. Taking over after the retirement of Judge Mark May, Johnson in August 2022 ordered the accused teen to stand trial on two counts of murder and other charges after finding that prosecutors had established probable cause. The teen later pleaded guilty to manslaughter counts and was sentenced in December 2022 to time in juvenile detention.
Johnson has also participated in the Advisory Committee on the Rules of Juvenile Procedure. Public searches of court dockets, appellate opinions, and news archives reveal no other widely covered landmark rulings or published appellate reversals specifically tied to Johnson’s decisions that have broadly reshaped Utah juvenile justice policy. Juvenile court records are frequently sealed, limiting visibility into routine caseloads involving dependency, delinquency, or family matters.
As Johnson prepares for retirement, the Third District Judicial Nominating Commission has advanced nominees to fill the vacancy. His bench service has emphasized due process protections for minors in serious cases, particularly where prosecutorial conduct raised integrity concerns.
