witness robert kushner , 32 , is one of more than a dozen former drug dealers testifying for the federal government about allegations of police wrongdoing .
witness robert kushner lost his varsity coaching job at a private academy after testifying this week about his years selling marijuana .
he told jurors tuesday that some of the undercover officers on trial had stolen $ 81,000 in cash and 7 pounds of marijuana from him .
history came as news to officials at jack m. barrack hebrew academy in suburban bryn mawr .