What Happened to Elizabeth Sullivan?

Disclaimer: This article contains mentions of murder. Reader discretion is advised.

The Dateline: Secrets Uncovered episode “Secrets by the Bay” will air on Oxygen on Wednesday, May 1, at 8 p.m. ET. It will follow the disappearance and murder of Elizabeth Sullivan while exploring the process of investigation and how her killer was caught. A synopsis of the episode reads, “A San Diego mother suddenly vanishes in 2014; nearly two years later, her body is found in the San Diego Bay, but medical examiners say that she has only been dead for a month or two.” 

Elizabeth Sullivan disappeared on October 13, 2014, after she was last noticed to be active on text. A 31-year-old wife of a Navy sailor, Elizabeth was a mother of two when she disappeared. CBS News reported that her phone was turned off shortly after she vanished, following which the San Diego police launched an investigation. Her family had also hired a private investigator and spread the word on social media. However, no leads were found, and the case subsequently went cold. 

According to People Magazine, on October 5, 2016, Elizabeth’s decomposed body was pulled from San Diego Bay in California. After a homicide investigation was initiated, police noted that Elizabeth’s husband, Matthew Sullivan, had moved to Maryland with his fiancee Kayla Turner, his two daughters, and the couple’s newborn. A neighbor claimed that Turner had moved in with him only two months after Elizabeth passed away. 

NBC San Diego reported that Matthew and Elizabeth Sullivan had custody disputes over their daughters. Police also found that there was a history of domestic violence in the relationship. 

Who killed Elizabeth Sullivan?

Matthew Sullivan was charged with the killing of Elizabeth in January 2018. When authorities searched the couple’s home, they found Elizabeth’s blood on the carpet. There was also blood on the wooden floor of the bedroom and a knife, which had traces of the victim’s blood, under the attic insulation. Police learned that Matthew brought a carpet cleaner on the day Elizabeth disappeared, The San Diego Union-Tribune reported. 

However, the defense argued that Elizabeth was prone to self-harm and likely cut herself with the knife that was found. They argued that she was prone to cutting herself when she was under severe stress. The Los Angeles Times noted that it was alleged that she might have hidden the knife under the attic herself. They further emphasized that Matthew had no criminal record. Elizabeth was allegedly prone to drug abuse and often didn’t come home at night. 

On the other hand, the prosecution claimed that Matthew Sullivan stabbed and killed Elizabeth while their daughters were in a different room. He then reportedly stored her body in a small freezer and claimed she disappeared. Matthew allegedly dumped her remains into the San Diego Bay after he moved out of their home, according to another report by the People Magazine. He allegedly went ahead with the murder after she threatened that she would take $1000 from their joint bank account and would leave with their children. 

Matthew Sullivan was convicted of second-degree murder and was sentenced to 16 years in prison, Fox 23 reported.

“Secrets by the Bay” will air on Oxygen on Wednesday, May 1, 2024, at 8 p.m. ET.