Any headline that ends in a question mark can be answered by the word “no.”

Betteridge’s law is based on the assumption that if the publishers of a headline were confident that the answer was yes, they would have presented it as an assertion; by presenting it as a question, they are not accountable for whether it is correct or not.

The law is named after Ian Betteridge, a British technology journalist who wrote about it in 2009. The maxim has been cited by other names since 1991, when a published compilation of Murphy’s law variants called it “Davis’s law”, a name that also appears online without any explanation of who Davis was. It has also been referred to as the “journalistic principle” and in 2007 was referred to in commentary as “an old truism among journalists”.