Former Collin County deputy William Armstrong has been arrested and charged with felony injury to a child in connection with the drowning death of 12-year-old Dylan Harrison during a scuba diving class last summer, authorities confirmed.
The tragic incident occurred on August 16, 2025, at The Scuba Ranch in Terrell, Texas, where Armstrong was serving as an instructor. According to witness affidavits obtained by the family’s attorney, the class included eight students, an instructor, and a dive master when things went horribly wrong for the young diver, as reported by local media.
Fatigue and False Statements
What makes this case particularly disturbing are the circumstances leading up to the tragedy. Records show that Armstrong had been awake for approximately 29 straight hours when he conducted the class. He had worked a full day as a deputy, followed by an overnight security shift at an investment firm before instructing the scuba class, investigators found.
The investigation also revealed troubling discrepancies in Armstrong’s account of events. According to an affidavit, when Able Springs Fire Rescue arrived at the scene, Armstrong was standing on the dock without diving gear. This directly contradicts his initial statement to investigators that he remained in the water searching for the missing child when first responders arrived.
“I will not take my eyes off your daughter,” the divemaster, Jonathan Roussel, allegedly assured Dylan’s parents before the class, as detailed in court documents. Yet Dylan’s body was later discovered away from the training platform at a depth of approximately 45 feet.
Technical Failures
Could proper weighting have prevented this tragedy? The affidavit indicates Harrison was most likely not weighted properly before descending, based on information retrieved from the dive computer she was wearing when she drowned.
Adding another layer to the case, when investigators asked to examine the divemaster’s equipment, Roussel claimed to have lost his own dive computer — a crucial piece of evidence that might have shed light on the timeline and circumstances of Dylan’s death.
Armstrong, who was a NAUI-sanctioned instructor at the time of the incident, resigned from his position with the Collin County Sheriff’s Office in October 2025. He has since been permanently suspended from teaching at The Scuba Ranch, diving publications note.
Legal Proceedings
After posting a $150,000 bail bond on February 6, 2026, Armstrong was released from the Kaufman County jail. He was seen walking out Friday afternoon, free while awaiting trial on charges that could result in significant prison time if convicted.
The Harrison family isn’t just seeking justice through criminal proceedings. Earlier in February, they filed a 40-page civil lawsuit against NAUI, PADI, and the dive operators and professionals involved. The comprehensive legal action alleges that systemic safety failures and deficiencies in training oversight within the diving industry contributed to their daughter’s death.
For the parents who entrusted their child’s safety to certified professionals, the legal battles ahead represent not just a quest for accountability, but a mission to ensure no other family experiences the devastation of losing a child during what should have been a supervised learning experience.
