Mealey's ( July 21, 2015, 10:16 AM EDT) -- BALTIMORE — Expert witnesses for the U.S. government in a case alleging that actions of the operator of a mobile X-ray business in committing Medicare fraud caused the deaths of four people can testify as to the “but-for” causation of death standard for two of the deceased patients but cannot testify about the but-for cause of bodily injury because the government relies on an incorrect definition of that standard, a Maryland federal judge held July 14 (United States of America v. Rafael Chikvashvili, No. 14-0423, D. Md.; 2015 U.S. Dist. LEXIS 91680)....