Does Isis really 'claim every terror attack'? How do we know if a claim is true?

Samuel Osborne

In recent years a routine has developed in the aftermath of major terror attacks: as details about the latest atrocity are revealed, the media will rush to publish the breaking news that Isis have claimed responsibility.

The eagerness to publish apparent Isis propaganda has understandably been met with backlash, with commentators dismissing the terror group's claims as an opportunistic attempt to spread terror and admonishing the media for drawing greater attention to them.

However, despite the popular misconception, it is false to suggest Isis claim every major terror attack.