Sir Thomas Hetherington is the Director of Public Prosecutions, the man who has to decide whether to prosecute in important or difficult cases, which charges to lay and whether it is in the 'public interest' to do so. He makes crucial decisions in th... (more)e areas of obscenity, race relations and criminal justice. Robin Day talks to the DPP about accountability, his professional role and some of the hotly-debated decisions he has made.