UK prime minister Boris Johnson has promised to take steps to protect military personnel from what he describes as ‘vexatious’ legal claims. It’s a controversial stance as armed conflicts, from Northern Ireland to Iraq, have thrown up serious allegations of criminal wrongdoing by soldiers. Stephen Sackur interviews Alexander Blackman, who was convicted of murder while serving in Afghanistan in 2011. What does his case tell us about morality and accountability on the frontline? Show less