Liam McAtasney is accused of strangling 19-year-old Sarah Stern in her Neptune City home before disposing of her body in the Shark River in Belmar.
Prosecutors allege that McAtasney killed Stern over roughly $8,000 that was in her home. He apparently thought he was going to get $100,000 but was mistaken about amount of cash, Assistant Prosecutor Meghan Doyle told jurors.
Stern was last seen at her home on the night of December 2, 2016. Hours later, her unoccupied vehicle was found on the Route 35 Bridge over the Shark River Inlet with the keys still in the ignition.
Her body has never been found.
Authorities believe McAtasney dumped the body with the help of his friend, Preston Taylor, who was Stern's former prom date and McAtasney's roommate at the time.
Taylor has pleaded guilty and began testifying Wednesday as the prosecution's star witness.
He said McAtasney told him Stern had the "type of money somebody would kill for" and that the plan was to get her drunk and take the money left to her by her mother, who had died while they were all in high school.
"Specifically decided that Liam would strangle her," he testified. "Any other way, any type of weapon, would have been too messy, would have left a whole lot of evidence. And then as far as what to do with her after she was dead, we talked about a couple plans. Bury her down at the campsite that Liam's dad owns, leaving her at the house, and then ultimately, we decided that the best way to go about it would be to make it look like a suicide."
McAtasney has denied everything.
"The defendant murdered her and made sure the body will never be found," Doyle said in her opening statement. "Strangled the life out of her...dumped her like garbage."
Defense Attorney Carlos Diaz-Cobo countered that there was no physical evidence to support the accusations and claimed a witness will testify that he or she saw the victim walking away from her car on the bridge.
The state is seeking a life sentence without parole in the case against McAtasney, who also faces charges of robbery, conspiracy, desecration of human remains and hindering apprehension. He has pleaded not guilty.
Taylor previously pleaded guilty to first-degree robbery, second-degree conspiracy to commit robbery, second-degree disturbing or desecrating human remains, two counts of third-degree hindering apprehension and fourth-degree tampering with physical evidence. He faces up to 20 years in prison and is subject to the No Early Release Act.
If convicted, McAtasney faces life in prison without the possibility of parole.
(The Associated Press contributed to this report)
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