Michael Grennier

South Plainfield Police Sergeant Michael Grennier stands next to an inmate phone in the booking room at the South Plainfield Police Department in 1999. (Star Ledger File Photo)

TRENTON – A former South Plainfield police captain and computer forensics specialist was sentenced today to 20 years in prison for paying a minor girl to live-stream sex acts on the Internet while he watched from his home computer, according to U.S. Attorney Paul J. Fishman.

Michael Grennier, 52, will also serve supervised release for life and be required to register as a sex offender.

Grennier pled guilty to one count of production of child pornography last year. He has been in custody since he was charged on Feb. 19, 2013.

According to U.S. Attorney Fishman:

On Feb. 14, 2013, Grennier enticed the minor to perform sexually explicit acts and stream images of herself over the Internet while he watched remotely from his home computer. He promised the girl he would buy her clothing in exchange for the performance.

Grennier directed the girl’s actions with text-message exchanges.

According to the complaint filed against Grennier in 2013, the former captain paid a minor girl for years to engage in sexual acts on the Internet. The complaint also alleged he paid for pictures of the girl naked, and on one occasion gave her and a second victim $500 to engage in sex acts in a hotel room. Grennier allegedly watched the encounter on a webcam, the complaint said.

At the time of his arrest, Grennier was working for a private computer forensics firm. Prior to his retirement, he was a computer forensics specialist for the South Plainfield Police Department.

Grennier was twice honored as South Plainfield's Officer Of The Year and had been considered for an international police award. The former captain was credited with aiding in the takedown of a global hacker's collective in the 1980s, according to a local South Plainfield newspaper.

Anthony G. Attrino may be reached at tattrino@njadvancemedia.com. Follow him on Twitter @TonyAttrino. Find NJ.com on Facebook.