In the article, May cites a submission by by Peter Davies (Chief Executive of the Child Exploitation and Online Protection center) as an example of why all Internet communications should be stored and made accessible to police without a warrant. Davies told the story of a murder that had been difficult to solve, and suggests that dragnet surveillance would have made the police's job simpler.
But as the Open Rights Group points out, the case in question is anything but a defense of bulk data-retention. Indeed, it involves a corrupt police officer who improperly used retained records to find information to pass on to a crime boss about a couple who were subsequently murdered. In other words, logging and storing information made it possible for a criminal and a corrupt cop to track people down.
It's nothing short of bizarre for Theresa May to cite this as a reason to retain more information, on more people, and to give access to that information to more agencies.
Tales of the Unexpected: the Communications Data Bill