RTFA: There was a court order, you can see a PDF of the judges' order linked right from the article. And you say there were no objections, but there were, by Twitter, who insisted that the subjects of the court-ordered release of data be given notice and the opportunity to appeal. Also, the court does not have to find that there are lives in danger when issuing a subpoena, only that there is reason to believe that a criminal act has occurred.