A guiding principle of credible communication – especially in crisis management – is to stay on message. This also applies on Twitter, as a German regional police force realized over the weekend.

Instead of being a trusted, reliable and authoritative source of reliable information, the Mannheim police ended up in a pointless feud on Twitter – even going as far as to point out another user’s punctuation mistake.

The exchange started after reports of a man driving a car into pedestrians in the German city of Heidelberg, which comes under the jurisdiction of police in nearby Mannheim.

When Twitter users started trolling the @PolizeiMannheim account with racist comments, the Twittering cops played into their hands by responding, instead of taking the high ground and ignoring or even blocking these users.

Inevitably, it turned into a shouting match – switching randomly into English. When you’re tweeting in a foreign language, it’s especially important to make sure your response is culturally acceptable to a mass audience.

One widely-quoted Mannheim police tweet included the phrase “WTF”, which frankly should not belong to the communications vocabulary of any professional organization.

German news magazine Stern has the full exchange (mostly in German). The police failed to keep control of the message by allowing themselves to be drawn in – and for resorting to making petty comments. Although grammar pedants will disagree, punctuation errors are not currently a punishable offense by law.

By this time, the conversation is going down a rat-hole – just like the police’s credibility on Twitter.

Police officers are trained not to rise to provocation while on the street. It’s time to extend this training to the staff who run their Twitter accounts.