Consider me extremely suspicious of this program. From WVTM:
Amtrak has asked the TSA to start screening some of its passengers against the Terrorist Screening Database watchlist maintained by the Threat Screening Center to see if known or suspected terrorists have been riding the rails, according to a U.S. Department of Homeland Security privacy impact document obtained by the Hearst Television National Investigative Unit.
The program, part of the Amtrak Rail Passenger Threat Assessment and which has not been previously reported, would compare personal passenger information from Amtrak – which may also later include a traveler's "publicly available social media" profiles viewed by DHS personnel – to the government's terrorist screening database.
If the TSA finds any matches, the agency would then provide Amtrak with statistical and anonymized results that would not include passenger names, at least for this initial stage.