How you get on US terrorism watch list, but have no way of finding out why
Social media posts or a single, uncorroborated source enough to blacklist someone, yet they're not told why, leaked government papers show

US authorities can place Americans and foreigners on a terrorist watch list indefinitely on the basis of vague rules without sound evidence, according to a leaked government document.
Once blacklisted, individuals have no way of finding out why they are deemed suspicious and even dead people's names remain on the list, under secret guidelines set out last year by the National Counter-Terrorism Centre(NCTC), which were published for the first time by The Intercept news website.
The government has built a vast system based on an unproven … premise
The rules introduced by President Barack Obama's administration represented an expansion of the government's power when it came to designating suspected terrorists, laying out broad criteria for adding names to the lists, The Intercept reported.
Individuals added to the watch lists could be banned from flying or subjected to additional searches and security screening at airports and border crossings.
The rules say government agencies can place a name on the watch list based on a "reasonable suspicion" but not on "unfounded suspicion or hunches", according to the 166-page document, entitled March 2013 Watchlisting Guidance.
"Although irrefutable evidence or concrete facts are not necessary, to be reasonable, suspicion should be as clear and as fully developed as circumstances permit," it said.
