When the chair of the U.S. National Transportation Safety Board appeared before the House Transportation and Infrastructure Committee this week, he was asked "Could you just tell us again in plain English why we don't know if this operator was on the phone three weeks after the accident?" He had trouble answering, because although the NTSB has detailed timestamped data for the engineer's cell phone records, and they have physical access to the phone and the phone's passwords, they can't figure out the data's time zones. The cell phone companies don't know either. My sources: Jaffe E. We still basically have no idea what happened with the Amtrak 188 derailment. CityLab 2015-06-04. http://www.citylab.com/commute/2015/06/we-still-basically-have-no-idea-what-... Nixon R. Phone data labyrinth hinders investigation of Amtrak derailment. New York Times 2015-06-05. http://www.nytimes.com/2015/06/06/us/inquiry-into-amtrak-derailment-is-slowe...