Mercer County Prosecutor Appoints Jessica Plumeri as Chief of County Detectives

Mercer County Prosecutor Angelo J. Onofri recently announced the promotions of six members of his investigative staff, including the second female chief of detectives in Mercer County history.

Jessica Plumeri was sworn in as chief of county detectives on July 31. Plumeri takes the helm after the August 1 retirement of Tracey McKeown, who was the prosecutor’s office first female chief.

“Jessica demonstrates the highest standards of professionalism, dedication to the safety of Mercer County residents, and a tireless pursuit of justice,” Prosecutor Onofri said. “She continues to break glass ceilings in law enforcement and our investigative staff is in good hands with her leadership.”

Raised in both Trenton and Hamilton Township, Plumeri attended Mount Saint Mary’s University in Emmitsburg, Maryland, graduating in 1994 with a bachelor’s degree in sociology with a concentration in criminal justice.

After college, she was hired as a detective with the Mercer County Prosecutor’s Office (MCPO). As her career progressed, Plumeri was assigned to the Special Investigations Unit where she began her passion for investigations involving the illegal distribution of narcotics.

In 1999, Plumeri entered the graduate program in education at The College of New Jersey and graduated with her master’s degree in teaching in 2001.

Upon returning to the prosecutor’s, Plumeri was assigned to the Trial Unit, assisted in homicide investigations, and returned to the Special Investigations Unit, where she served as a member of the Mercer County Narcotics Task Force.

In 2016, Mercer County Sheriff John A. Kemler appointed Plumeri undersheriff of the Mercer County Sheriff’s Office (MCSO).

In 2019, Plumeri returned to the Mercer County Prosecutor’s Office as deputy chief of detectives and has been responsible for the oversight of major crime investigations throughout the county.

She has also assisted the DEA as an undercover officer resulting in the seizure of large amounts of narcotics.

Also promoted were Captain Tarek Elkachouty to deputy chief; Lieutenant Matt Norton to captain; Sergeant Natischa Clark to lieutenant; Detective Brian Kiely to sergeant; and Detective Michael Castaldo to officer-in-charge.