Intelysis has for many years specialized in the investigation of Arson and suspicious fire cases. The practice is based on the experience of principal, David L. Ziegler who had 28 years experience with the Federal Bureau of Alcohol, Tobacco & Firearms (ATF) specializing in fire, arson and explosion cases. He is a certified fire investigator (CFI), a member of the International Association of Arson Investigators (IAAI), the Pennsylvania Association of Arson Investigators, and a Certified Fraud Examiner (CFE).

David Headed the ATF investigation into the largest commercial fire loss in the US, a 2.2 billion fire at One Meridian Plaza, Philadelphia, PA in 1991. As the investigator in charge of the case, he supervised the task force that gathered sufficient evidence to determine the origin and cause of the fire. He also led a complex investigation into to an organized crime syndicateresponsible for a serious arson case. David managed a three year probe for a Philadelphia based insurance company and his findings caused the insured to withdraw the claim and focused attention on the involvement of a local bank in the scheme.

In addition to providing investigative expertise in arson cases,Intelysis also provides fire and arson seminars for police, fire and insurance investigators in the Eastern Region. Over 500 professionals have attended these seminars in the last three years. David has been quoted in national law enforcement publications as a leading expert on arson for profit investigations. He has also served as a technical advisor to television production companies seeking expert direction in syndicated shows.