Baltimore Police Officer William Porter (R) and his attorneys Joseph Murtha (L) and Gary Proctor arrive at the courthouse for pretrial hearings in the case of Caeser Goodson in Baltimore, Maryland, in this file photo taken January 6, 2016. A Maryland judge on Wednesday rejected prosecutors’ request that Porter, facing retrial over the death of black detainee Freddie Gray, be forced to testify in the trials of his fellow officers. REUTERS/Bryan Woolston/Files