Long Island Music Teacher Indicted for Raping and Killing Sister-in-Law

By the Editorial Team · Thursday, July 30, 2026

Joseph Horner, a Long Island music teacher, has been indicted for the premeditated rape and murder of his sister-in-law, Victoria Castle, whom he attacked in her apartment after planning and rehearsing the assault. The case highlights the disturbing nature of the crime, as Horner maintained normal behavior during a FaceTime call with his wife shortly after the attack, and he is now held without bail pending further investigation.

A Long Island man has been indicted on charges of raping and killing his sister-in-law in a brutal attack that prosecutors say he planned and rehearsed in advance. Joseph Horner, 27, a music teacher in the Oceanside School District, was arrested on June 28 after allegedly breaking into the downstairs apartment of 25-year-old Victoria Castle, a doctoral student at Stony Brook University, and carrying out the assault.

Nassau County prosecutors revealed that Horner repeatedly entered Castle’s North Oak Street residence in North Massapequa to view explicit photos of his wife’s sister prior to the attack. He allegedly lured Castle under the pretense of needing help moving a keyboard before striking her from behind with a chokehold. Surveillance footage and photographs released by authorities showed Horner practicing the chokehold on a stuffed animal earlier on the day of the attack.

Assistant District Attorney Alexander DePalo detailed in court that Horner admitted to harboring sexual desires for Castle since 2017. “This defendant saw an opportunity to follow through on his sexual desires to be with the victim,” he said. Prosecutors described how Horner ambushed Castle without warning, applied the chokehold until she lost consciousness, then removed her clothing and raped her. According to prosecutors, following the assault, Horner calmly waited on the front doorstep for police to arrive.

Authorities said Horner was taken into custody at the scene, and Castle was rushed to a hospital where she was pronounced dead. The defendant pleaded not guilty during a court appearance Wednesday, as his wife—who was away on a bachelorette trip at the time—sat in court visibly upset and supported by her parents. Nassau County Judge Howard Sturim ordered that Horner be held without bail.

Prosecutors also disclosed that approximately 15 minutes after incapacitating Castle, Horner participated in a FaceTime call with his wife, during which he behaved as if nothing had occurred. Nassau County District Attorney Anne Donnelly highlighted the disturbing nature of this call, noting that Horner acted normally despite Castle lying unconscious just a floor below.

Castle had been living in the downstairs apartment of the family home where Horner and his wife resided. In a poignant social media post from several years prior, Castle expressed affection for her sister and Horner after their marriage, writing, “My sister, my person, my partner in chaos, is now married to one of the most wonderful people in the world. I love you both forever.”

The investigation remains ongoing as the community grapples with the circumstances surrounding this tragic killing.

This article was reported by synthesizing coverage from multiple independent news outlets to present a balanced, unbiased account. Read about our editorial standards. Spotted an error? Let us know.