An Atlantic City man who pleaded guilty to manslaughter in the death of New Jersey state trooper has lost his bid to have his 30-year prison sentence set aside.

The trooper, Bertram Zimmerman III, was killed in February 2004 while responding to an armed robbery at a Dennis Township convenience store. The 32-year-old trooper died when his patrol car struck a utility pole.

Middleton Dunmore, who admitted robbing the store, eventually pleaded guilty in 2006. He received a 20-year term for that robbery and others he committed in Cape May County, and a 10-year term for the manslaughter charge.

Dunmore claimed he received ineffective legal representation at the time.

But Superior Court Judge Raymond Batten rejected those claims Wednesday during a hearing attended by Zimmerman's family and dozens of troopers.

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