I couldn't find an English version yet. Basically, during an internal affair inquiry, detectives found that a police officer had contacted a journalist. They asked a judge to issue several warrants to be able to get DNR (dial number recorder) from the journalist's iPhone and, according to this article, they were able to activate the iPhone's GPS to follow the journalist.
About the GPS: I didn't know it was possible to do this (is the signal transmitted to the carrier?).