FREEHOLD BOROUGH —The last defendant in the Sarah Stern murder case was sentenced Friday to 18 years in prison for his role in the 2016 slaying.

Preston Taylor, 22, will have to serve 15 years before he is eligible for parole.

Taylor and Liam McAtasney, 21, were convicted of killing the 19-year-old at her Neptune City home and then throwing her body off the Route 35 bridge, where they left her car to make it appear like a suicide. Stern's body has never been found.

Taylor pleaded guilty and agreed to testify against McAtasney, who denies killing Stern despite a chilling confession captured in a secretly recorded video. In the video, McAtasney said he choked Stern to death, keeping track of the minutes as he watched her struggle and urinate herself.

McAtasney's lawyer argued that the taped confession was an act to impress a horror filmmaker friend.

Liam McAtasney, left, and Preston Taylor at their pre-indictment hearing in Freehold (Thomas Costello, Asbury Park Press pool photos)

Taylor testified that the murder plot was meant to steal Stern's cash inheritance from her mother, which McAtasney also explained in the undercover video.

Taylor and McAtasney were roommates and had been friends with Stern. The three had attended Neptune High School together and Taylor and Stern attended their prom as a couple.

On Friday, Taylor apologized for being part of the plan and wished he had done more to stop it, according to Asbury Park Press coverage of the sentencing.  According to the Press, Sarah Stern's father Michael walked out of the courtroom when Taylor began to speak and returned when he was done.

Liam McAtasney is sentenced to life in prison with no chance of parole for the murder of Sarah Stern in the courtroom of Judge Richard W. English at the Monmouth County Courthouse in Freehold, NJ Friday June 21, 2019. ASBURY PARK PRESS PHOTO BY TANYA BREEN

As part of his plea deal, Taylor admitted helping McAtasney throw Stern's body off the bridge when McAtasney was unable to lift it. Taylor said that McAtasney told him if that if he was ever questioned about Stern’s disappearance, he should say she had had a falling out with her father and had attempted suicide.

Taylor pleaded guilty in May 2017 to charges of first-degree armed robbery, second degree conspiracy, second-degree desecration of human remains, third-degree hindering apprehension of oneself, third-degree hindering apprehension of another and fourth-degree tampering with evidence.

Liam McAtasney in a secretly recorded video in which he confesses to killing Sarah Stern in 2016. (NJ.com via YouTube/File photo)

McAtasney was sentenced last Friday to life in prison with no chance of parole for the murder. He was sentenced to concurrent terms of 20 years for first-degree robbery and five years for third-degree hindering. He must first serve a consecutive 10-year sentence for disturbing or desecrating human remains.

It was the mandatory sentence for the conviction in the December 2016 slaying.

More Jersey Shore News: