Dr. Harrison is a lifetime firearms enthusiast and aquatic sports competitor.  He is very familiar with firearms technology, is a licensed shooting instructor and range safety officer, and was a successful marksmanship competitor with prior U.S. military service.  He has an avid interest in ocean sports and related equipment including surfboard, sailboard, SCUBA, kitesurfing, and snowboard inventions and designs. He has been deposed and cross-examined as a technical expert, and has also taken depositions of technical experts as a lawyer.