Trooper Bertram Zimmerman died following was responding to a robbery call in 2004, when he was involved in a deadly crash. (New Jersey State Police) DENNIS TOWNSHIP, N.J. - New Jersey State Police are asking for the public's assistance in identifying the suspect or suspects responsible for vandalizing a memorial for a fallen trooper.On Wednesday, troopers responded to the memorial on State Highway 83 where they came across the defaced memorial.Investigators say those responsible used white caulk to write a derogatory phrase on the pavers and defaced the front of the granite monument at the center of the memorial.The memorial is dedicated to the memory of Trooper Bertram Zimmerman.