The 54-year-old Harrison will step down as police commissioner sometime in December 2023, a department spokesperson told Daily Voice.
Suffolk County Police Chief of Department Robert Waring will take over the department’s operations until a new commissioner is named.
Harrison, who grew up in the South Jamaica section of Queens, was nominated as commissioner by Suffolk County Executive Steve Bellone in December 2021 after spending 30 years with the New York City Police Department.
He was unanimously approved by the Suffolk County Legislature and was sworn in in January 2022.
The move followed Harrison’s nine-month stint as NYPD chief of department.
Before that, he was promoted to chief of detectives in December 2019, making him the first Black person to hold the position since the agency’s founding in 1845.
Upon taking over as Suffolk County’s top cop, Harrison said solving the Gilgo Beach serial murders case was a priority.
“We will not rest until we bring those accountable to justice,” he told reporters while touring the investigation site in December 2021. "I don’t know what the odds are, but I’d put my money on the Suffolk County investigators.”
Nineteen months later, in July 2023, detectives arrested 59-year-old architect and married father of two Rex Heuermann on three counts of first-degree murder in the case.
Heuermann, of Massapequa Park, is charged with murder in the deaths of Melissa Barthelemy, Megan Waterman, and Amber Lynn Costello at Gilgo Beach, located off the south shore of Suffolk County.
He is also the primary suspect in the disappearance and killing of Maureen Brainard-Barnes.
Heuermann has pleaded not guilty to all charges.
As for Harrison, after two years of leading one of the largest police departments in the country, he says he plans to spend more time with family.
"I'm going to be utilizing my time. I won't be around, but I'll still be in a position when and if people need to ask my opinion on something,” he told ABC7.
Harrison’s departure comes as Suffolk County Executive Steve Bellone, a Democrat, nears the end of his fourth three-year term, making him ineligible to run again.
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