David has been a trial lawyer for over 30 years.   In that time he has seen the nature of testimony change from the memory centered witness of the last century to the document centered witness of the first few decades of the present one.   He has taught law students in law school and accounting students in business school how to adapt to these changes. As an expert witness himself, David has faced these changes first hand.  Now, he is facing the "third revolution" of the virtual courtroom.