Chief Garth W. Warner

Chief Warner was raised and has lived and worked in Derry Township nearly his entire life.  Both of his grandfathers worked in the Hershey Chocolate Factory and his grandmother worked for the Milton Hershey School. Chief Warner graduated from Hershey High School in 1983.  One of his first jobs, like many teens living in Hershey, was at Hersheypark, eventually working in the Security Department.  During that time, he developed an interest in the field of Law Enforcement.  He passed entry into and paid his own way through the 32nd Municipal Police Academy at Harrisburg Area Community College.  Immediately after graduation from the Police Academy in April 1985, he was hired part-time and started work for the Highspire Borough Police Department at the age of 19.

In September 1985 he was hired full-time by South Londonderry Township Police Department in Lebanon County.  In addition to his Patrol Officer responsibilities, he worked as an evidence technician and photographer.

Chief Warner joined the Derry Township Police Department in March of 1988.  During his tenure with Derry Township, Chief Warner has served in the Department’s Traffic Safety Section and is one of the Department’s certified Traffic Accident Reconstructionists.  His assignment for over 20 years was the K9 Unit.  Chief Warner worked with partners Rex, Jet, and Renko during that time.  He also serves as one of the Department’s Employee Assistance Peer Support Officers.  Chief Warner was promoted to Lieutenant of Operations in 2012 and appointed as Chief of Police in 2016.

Chief Warner is a member of Dauphin County Chiefs of Police Association (Past President and current committee chair), Central Pennsylvania Chiefs of Police Association, Pennsylvania Chiefs of Police Association, and the International Chiefs of Police Association.  He is also a member of the North American Police Work Dog Association and the FBI Law Enforcement Executive Development Association.

Lieutenant Robert F. Demmel

Lieutenant Demmel was born and raised in Derry Township and graduated from Hershey High School in 1988. After high school, he attended Shippensburg University where he received a Bachelor of Science degree in Criminal Justice and Psychology. While attending Shippensburg University, Lt. Demmel completed an internship with the Derry Township Police Department.   

Lieutenant Demmel attended the 57th Municipal Police Academy at Harrisburg Area Community College and began his law enforcement career part-time with the Hummelstown Borough Police Department. In 1995 he began working full-time with the Palmyra Borough Police Department where he spent 3 years as a patrol officer and member of the Lebanon County Drug Task Force.   

In May 1998 Lt. Demmel was hired along with Lt. Roche at the Derry Township Police Department. Lieutenant Demmel served 6 years as a police officer in the patrol division and 7 years as a detective in the criminal investigation section. He was promoted to the rank of Sergeant in May 2011. As a sergeant with Derry Township, he was assigned to the patrol division as a Platoon Sergeant, the Community Services Unit Sergeant, and the Criminal Investigation Section as a Detective Sergeant.   

Lieutenant Demmel was a member of the Capital Region Forensics Unit and the Dauphin County Accident Reconstruction Team for approximately 20 years. He has been certified as a polygraph examiner since 2000. Lt. Demmel has served on the Derry Township Special Enforcement Team, the Mountain Bike Unit,  and the Forensic Unit. He has also served as a Field Training Officer, a Taser instructor, a Baton instructor, and an OC instructor.  

Lieutenant Demmel was promoted to the rank of Lieutenant/Assistant Chief of Police in April 2022. He continues to serve as a member of the Dauphin County Rapid Response Team, the Derry Township Mountain Bike Unit, and as a Drone Operator on the Drone Unit.