Jurors have convicted a Monmouth County man of gunning down three family members and a family friend with a high-powered rifle when he was a teenager on New Year's Eve in 2017.

The panel found Scott Kologi, 20, guilty of murder and a weapons offense on Thursday.

Kologi was 16 when police were called to his family's Long Branch home just before midnight on New Year's Eve in 2017. They found four people shot at various locations inside the home. The victims were Kologi's 42-year-old father, Steven Kologi; his 44-year-old mother, Linda; his 18-year-old sister, Brittany; and his grandfather’s companion, 70-year-old Mary Schultz of Ocean Township.

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Kologi's grandfather, brother and another family friend were able to escape unharmed.

Defense attorneys had pursued an insanity defense.

“This trial hinged on issues of mental health and the responsibility of this defendant," acting Prosecutor Lori Linskey said in a statement. “It is clear that the jury considered all of the evidence, including testimony of expert witnesses, as well as the applicable law, in rendering its verdict.”

Kologi faces up to life in prison when he is sentenced in June.