Three local black men including Winston Silcott were convicted of PC Blakelock 's murder in 1987 , but their convictions were quashed in 1991 .
Winston Silcott remained in prison for a further 12 years for another murder .
Three local black men including Winston Silcott were convicted of PC Blakelock 's murder in 1987 , but their convictions were quashed in 1991 , although Silcott remained in prison for a further 12 years for another murder .