Why are armed police stepping back from their duties?

Available for over a year

In British policing tradition, most frontline officers don't carry firearms when they patrol the streets. That's a task left to specialist firearms officers who've recieved extra training before being given permission to carry guns. But what happens when this system breaks down? A recent decision to charge one firearms officers with the murder of 24-year-old Chris Kaba prompted many others to step back from their duties. It even led to the Metropolitan Police requesting extra support from other UK police forces and the military. For 5 Questions On, the BBC's Home Affairs Correspondent Tom Symonds explains what's going on with armed police in the UK.