An eastern Iowa human rights activist claims racism played a dominant role in a criminal case that’s put a black man behind bars.An all-white jury Thursday convicted a black Marshalltown man guilty in the 1998 robbery of a Calamus convenience store. 18-year-old Tony Washington will be sentenced next month. Clinton Human Rights Commission chairman Reverend Lyle Davis says racism, not evidence, led the jury to reach the guilty verdict. The county attorney dismisses the Reverend’s allegation.