Joseph Horner, a 27-year-old music teacher from North Massapequa, New York, has been arrested for the alleged sexual assault and murder of his sister-in-law, Victoria Castle, according to the Nassau County Police Department. The incident occurred on Monday, June 29, at their shared home on North Oak Street while Horner's wife was out of town attending a bachelorette party.
Attack and Arrest
Prosecutors allege that Horner asked Castle, a 25-year-old PhD student at Stony Brook University, to help him move a piano. He then attacked her from behind, placing her in a chokehold until she lost consciousness. After disrobing her, he raped her, the district attorney's office said. Following the assault, Horner called 911 at approximately 8:45 a.m. and waited for police to arrive. He immediately admitted to detectives that he had choked and had sex with his sister-in-law, prosecutors said. He was arrested at the scene and charged with second-degree murder. Emergency services transported Castle to a local hospital, where she died less than an hour after the 911 call.
Obsession and Legal Proceedings
Investigators revealed that Horner had been obsessed with Castle for nearly a decade. He met both his wife and Castle in 2016 and had harbored a twisted fascination with her since 2017, according to the Nassau County District Attorney's Office. Horner, who taught music in the Oceanside School District, lived in the upstairs apartment of the multi-family house with his wife, while Castle occupied the ground-floor unit. At his arraignment, Horner pleaded not guilty and is being held without bail. His attorney, Gregory Grizopoulos, stated, "These are very serious and disturbing allegations, and there’s a very stark contrast between the allegations and his beloved reputation that he had as a teacher, with both his students and his fellow teachers." Grizopoulos added, "His family is devastated by the loss of their family member, Victoria, as well as the allegations against their son, Joe. We’ll continue to evaluate the evidence as more details are disclosed to us."
School District Response
The Oceanside School District placed Horner on administrative leave following his arrest. The superintendent released a statement to News12 Long Island, expressing shock at the allegations but did not provide further details. The case continues to develop as authorities investigate the circumstances surrounding the tragic death of Victoria Castle.
