Princeton Man Charged In Brother’s Death Agrees To Pretrial Detention

PRINCETON, NJ — Matthew Hertgen, charged in the murder of his brother, made his first in-person court appearance on Thursday morning. He agreed to a pretrial detention.

Wearing an orange jumpsuit, Matthew appeared alert throughout the proceedings at the Mercer County Superior Court. He will be held in jail until trial on murder and other charges begin.

He was represented by public defender Jason Matey. Tim McCann represented the state.

Matey and the presiding judge confirmed with Matthew Hertgen that he was agreeing to pretrial detention willingly.

He has seven days to file an appeal if he changes his mind about the pretrial detention, Matey explained.

There were a few people present during the hearing, who left promptly after proceedings ended.

The judge set Matthew Hertgen’s next court appearance for March 24.

The 31-year-old is charged with first-degree murder, along with various third and fourth-degree weapons offenses related to possession of a knife and a golf club in connection with the death of his brother Joseph Hertgen, 27.

When he was taken into custody, Matthew Hertgen told police he "went into a fit of madness, maybe like forty minutes ago."

The affidavit of probable cause released Thursday evening shed more light on the gruesome scene that awaited police officers when they entered the Hertgen home on Feb. 22 at Michelle Mews, Princeton.

Officers found Joseph Hertgen’s body on the floor, with a pool of blood around his head and torso, the complaint said. They found a cup of what they believed to be blood, along with blood-smeared utensils and a plate on the dining table next to Joseph’s body.

There was also a dead cat on an ottoman in the living room. The cat had suffered blunt force injuries and was also partially burned, the complaint said.

A family member told investigators that Matthew Hertgen suffered from severe mental illness for the past five years. On Feb. 22, Matthew was extremely "distressed, despondent, and experiencing terrifying visions," he told investigators.

The brothers, who grew up in Toms River, played soccer at and graduated from Toms River North - Matthew in 2011 and Joseph in 2016. Both continued to play soccer in college, with Matthew at Wesleyan and Joseph at the University of Michigan

Joseph Hertgen worked as an Analyst for Locust Point Capital in Red Bank, NJ since 2023.

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