Victoria Castle had just started her summer break from Stony Brook University, where she was working toward her PhD. The 25-year-old was looking forward to celebrating with friends and family — unaware that her brother-in-law allegedly had darker plans in mind.
According to the Nassau County District Attorney's Office, Joseph Horner, a 27-year-old music teacher in the Oceanside School District, had been fixated on Castle since he met her around 2016 when he first started dating his wife. For nearly a decade, that obsession festered while he lived in an upstairs apartment of a multi-family home on North Oak Street in North Massapequa with his wife, and Castle occupied the ground-floor unit.
Background
The tragedy unfolded on a Monday morning as Horner's wife was hundreds of miles away, attending a bachelorette party. Prosecutors say Horner saw his opportunity when his sister-in-law agreed to help him move a piano inside their shared residence.
"He asked her to help move a piano," Nassau County District Attorney Anne Donnelly said at Horner's arraignment. "Then he attacked her from behind — placing her in a chokehold until she went limp."
After rendering Castle unconscious, Horner allegedly disrobed her and sexually assaulted her, according to prosecutors. The DA's office described the attack as premeditated, noting that Horner had waited years for an opportunity to act on his desires.
"This is not a crime of passion," Donnelly said. "He planned this. He knew exactly when his wife would be gone."
The Investigation
Following the brutal assault, authorities say Horner called 911 himself around 8:45 a.m. and waited for police to arrive at the scene. When detectives arrived, he immediately admitted to choking his sister-in-law and having sexual contact with her without consent.
"He made statements incriminating himself," Nassau County Police Commissioner Patrick Ryder said during a press conference.
Emergency responders rushed Castle to a nearby hospital where she was pronounced dead less than an hour after the initial 911 call. The medical examiner's office is expected to determine the exact cause of death, though prosecutors have indicated strangulation as the primary mechanism.
Investigators executed a search warrant at the North Massapequa residence and collected evidence from both apartments. Horner was arrested at the scene and charged with second-degree murder.
Key Takeaways
- Victoria Castle, 25, was a PhD student at Stony Brook University and lived in the ground-floor unit of her brother-in-law's multi-family home
- Joseph Horner allegedly confessed to police that he choked his sister-in-law and sexually assaulted her after luring her with a piano-moving request
- Prosecutors say Horner had been "lusting" over Castle since approximately 2017 — nearly nine years before the killing
- The suspect is a music teacher in the Oceanside School District, where he has been placed on administrative leave
- He is being held without bail and has pleaded not guilty to second-degree murder
What's Next
Horner is scheduled to appear in Nassau County Court for a preliminary hearing as prosecutors continue building their case. The DA's office said additional charges related to sexual assault are expected to be filed as the investigation progresses.
The Oceanside School District released a statement expressing shock at the allegations, with Superintendent Dr. Phyllis Harrington calling Horner's reputation among students and colleagues "beloved."
"These are very serious and disturbing allegations," said Gregory Grizopoulos, Horner's defense attorney. "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."
Castle's family has not yet made a public statement regarding the tragedy.