From a New York Times business section article on journalist Glenn Greenwald's resignation from the Intercept: "At the time of the leaks, Mr. Greenwald worked for the United States edition of The Guardian newspaper, and the aggressive reporting he conducted with two colleagues, Ewen MacAskill and the documentary filmmaker Laura Poitras, gave The Guardian US the Pulitzer Prize in service journalism in 2014."
The 2014 Pulitzer won by The Guardian US was for public service, not "service journalism," which is a term for how-to articles that help readers do things: "How to be productive while working at home," "How to renovate your kitchen without losing your mind," etc. There is no Pulitzer Prize in "service journalism," unfortunately for the hardy souls who churn out these articles, which do, when well done, provide a service to readers, though less glamorously than the investigative crusades that often win the Pulitzer for public service.