THE former Minneapolis police officer convicted of murdering George Floyd has pleaded not guilty to violating a teenager's civil rights by using a neck restraint similar to the one that killed Floyd, a Black man whose death galvanized a national protest movement against racism. In the current case, the former officer, Derek Chauvin, who is white, stands accused of violating the rights of a then-14-year-old Black boy in 2017 by hitting him with a flashlight and holding a knee on his neck while he was prone, handcuffed and not resisting arrest. Chauvin, now imprisoned for 22-1/2 years for Floyd's murder,…