There was a lot of racism within the Metropolitan Police at the time & a lot of mistakes were also made. The families efforts to get justice for their son were the main reason this case never went away, thankfully. Without the double jeopardy law change, the advance in DNA testing which was unable to detect the blood on the jacket previously, would never have been used to convict these scum. Surely if evidence, either scientific or other, is found then the chance to retry someone is something that should be available.