Although he now resides in Aventura, Florida, Dr. Charles Humble lived in Greater Indianapolis, Indiana, for decades. He holds an associate of arts in criminology from Indiana University–Purdue University Indianapolis and a bachelor of science from Indiana Christian University in Noblesville, Indiana. Dr. Charles Humble ultimately returned to his Indiana Christian University alma mater to receive an honorary PhD.

Dr. Humble served in the Indianapolis Metropolitan Police Department from 1969 to 1974, working as a patrol officer, motorcycle officer, and field investigator. While off-duty, he apprehended three murder suspects without any assistance or backup and was awarded the departments 'Commendation for Outstanding Devotion to Duty'.

From 1974 to 1998, he conducted voice stress analysis truth verification examinations for a variety of law enforcement agencies and private companies as the president of Indianapolis’ Humble and Associates. In 1988 he developed the patented Computer Voice Stress Analyzer (CVSA) and formed the National Institute for Truth Verification (now NITV Federal Services) and relocated to West Palm Beach, Florida. NITV FS is now the world leader in truth verification technology with over 2,500 law enforcement clients in the US alone, including the Atlanta P.D., Illinois State Police, California Highway Patrol, New Orleans P.D. and the US Federal Courts.