On Boxing Day 1994, 27-year-old gynaecologist Dr Joan Francisco was found strangled in her London flat - but her family faced an agonising five-year legal battle before her volatile ex-boyfriend was finally brought to justice. Did police and prosecutors treat them differently because they were black? Award-winning crime writer Stephen Wright talks to Joan’s sister Margaret about how the Stephen Lawrence case inspired the family to pursue a landmark civil case, their joy at finally getting ‘Justice for Joan’, and the lessons that the case offers for the Black Lives Matter movement.