State Corrections records show that Stayback died on Jan. 16, a week after his 70th birthday, at South Woods State Prison in the Cumberland County town of Bridgeton.
The River Vale native was scheduled for parole in mid-2018.
Stayback, who resigned before being indicted after 29 years as a patrol officer, was arrested on July 9, 1999 on charges of molesting three girls.
Further investigation found two victims who said he'd fondled them seven years earlier.
The victims ranged in age from 8 to 15 and were molested at his homes in River Vale and Hillsdale.
Stayback rejected an offer of 12 years in prison from the Bergen County Prosecutor's Office in exchange for a guilty plea and instead went to trial.
Jurors in 2001 convicted Stayback after four days of testimony and two days of deliberations.
A total of 28 guilty verdicts included charges of sexual assault, criminal sexual contact and child endangerment.
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