[HIGHLIGHTS] Controversial concert: Washington in turn accuses a former member of Pink Floyd of "anti-Semitism"

U.S. joins German investigation into Roger Waters' alleged anti-Semitism.

Waters wore outfit reminiscent of an SS officer at a concert in May in Berlin, Germany. The British singer is being investigated "on suspicion of incitement to hatred" Waters, 79, has also distinguished himself in recent years by defending actions to boycott Israeli products in the name of defending the Palestinian cause. He accused his critics of "bad faith" in a message posted Friday night on his Instagram and Twitter accounts.