Just three weeks after becoming prime minister, Andy Burnham is already unpicking a key piece of legislation passed under his predecessor Sir Keir Starmer. After ordering a review, Burnham announced that he would exclude most rapists, child sex offenders and members of grooming gangs from the legislation. But that left many people convicted of manslaughter still eligible for early release, including two of the men convicted of the manslaughter of PC Andrew Harper - prompting outcry from his family and former colleagues. Burnham now says he is "increasingly confident" of being able to prevent the early release of "other serious offenders" including PC Harper's killers. But how might he do that and why have the options he is looking at been previously rejected?