Zimbabwe’s president does a good turn to journalists by grabbing the hand of politicians and royals, making major news out of so-called “gaffes” by UK home secretary Jack Straw and even Prince Charles. But what happens when a journalist seeks out the hand of a war criminal?

The BBC took credit this week for uncovering Afghan warlord Faryadi Zardad, who was living in London under a false passport. Tracked down by John Simpson, its star correspondent and the self-styled liberator of Kabul, the broadcaster repeatedly showed a clip of the journalist arriving with a TV crew at the non-descript terraced house in which Zardad was holed up before his arrest and unprecedented prosecution on English soil for crimes committed abroad.

Seeking to show how its intrepid reporter unmasked the truth in an “exclusive” for the BBC’s flagship news programme Newsnight, every broadcast reporting Zardad’s 20-year conviction showed Simpson in a handshake with a man who, the broadcaster delighted in explaining, kept a human “dog.”

The point is not that Simpson made a mistake. It’s just that accidental handshakes should not distract reporters and editors, especially when such actions mean nothing more than juvenile embarrassment.