When police officers shoot people under questionable circumstances, Dr. Lewinski is often there to defend their actions. He has testified in or consulted in nearly 200 cases over the last decade. His conclusions are consistent: The officer acted appropriately, even when shooting an unarmed person. Even when shooting someone in the back. Even when witness testimony, forensic evidence or video footage contradicts the officer's story. He has appeared as an expert witness in criminal trials, civil cases and disciplinary hearings, and before grand juries. In addition, his company, the Force Science Institute, has trained tens of thousands of police officers. His research has been roundly criticized by experts. An editor for The American Journal of Psychology called his work pseudoscience." The Justice Department denounced his findings as "lacking in both foundation and reliability." Civil rights lawyers say he is selling dangerous ideas. In the protests that have followed police shootings, demonstrators have often asked why officers are so rarely punished for shootings that seem unwarranted. Dr. Lewinski is part of the answer. In testimony on the stand, for which he charges nearly $1,000 an hour, he ... sprinkles scientific explanations with sports analogies. Dr. Lewinski and his company have provided training for dozens of departments. His messages often conflict, in both substance and tone, with the training now recommended by the Justice Department and police organizations.