Khalid Turaani knows what it's like to be on a secret government watchlist.He learned about his status on it, not from an official letter or communication, but when TSA officers stopped him from flying one day in 2017."They told me that I am on the no-fly list and that I cannot board that flight," Turaani recalled in an interview. Results from a public records request he submitted that same year to the Department of Homeland Security confirmed – in writing – what he suspected: that his name had been assigned "no-fly" status. With the help of an attorney at the Constitutional Law Center for Muslims in America, Turaani successfully challenged the designation through the formal redress process. In December 2017, DHS sent him a letter, writing that it had "made any corrections" including those "that may assist in avoiding incidents of misidentification" but never disclosed why Turaani had been on the list in the first place. He has not been blocked from flying since. The attorney working on his behalf shared those documents with Hearst Television."So much harassment," Turaani said. "And it was really frustrating. And to tell you the truth, it was also humiliating."Amtrak to screen passengers against watchlistSoon, more people may find themselves ensnared by the same screening.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.READ the government document that reveals the existence of a program to screen Amtrak passengers against a terrorist watchlist; obtained by Hearst Television National Investigative Unit.Currently, airline passengers can opt out of watchlist screening by choosing not to fly. But Amtrak passengers apparently won't have that option because the screening will initially use "several months" of past travel on the busy Northeast Corridor, according to the threat assessment privacy document. Amtrak routes go through 46 of the 50 states. A spokesperson for the railroad did not respond to a question about whether passengers will be able to ask Amtrak to exclude past travel from the new screening.'It's terrifying to me' The details of the plan are laid out in a 12-page Privacy Impact Assessment. As it notes, the 9/11 Commission report stated that while aviation remains a possible target, "opportunities to do harm are as great, or greater, in maritime or surface transportation." Congress raised the possibility of a security watchlist program for Amtrak as far back as 2007 and again suggested a vetting system more than decade later, the DHS document also notes. In 2020, just before the coronavirus pandemic began, Amtrak said it was assigning more police officers onboard its trains after a spike in crime.The new watchlist screening program, however, is raising alarm among civil liberties advocates, who say it compromises too much liberty in the name of increasing safety."It's terrifying to me,” said Saira Hussain, a staff attorney at the Electronic Frontier Foundation (EFF), who learned about the new program from the National Investigative Unit.In the Privacy Impact Assessment, DHS acknowledges that mistakes and wrong matches are possible, disclosing "there is a risk that limited information provided by Amtrak will result in inaccurate watchlist match results."The assessment goes on to assert that incorrect matches will have "no impact" on individual passengers' privacy because only past travel records will be used and only statistical, or anonymized, results will be given to Amtrak. That means no passengers who are positive for a watchlist match will have their identities turned over to Amtrak. The limitation would be in place for at least in the initial phase of the program. But even then, the impact on travelers could go beyond TSA or Amtrak.In the same document, DHS notes that the information gathered could be used for other purposes, including that potential and confirmed matches may be shared "with other law enforcement agencies pursuant to established routine uses."Hussain said in an interview she "absolutely" worries about the effect of mistakes on individuals."It can increase the chances of them facing some really negative outcomes when it comes to a contact with law enforcement. Should they be stopped for, you know, for like a broken tail light or something like that," she said.'Mission creep'"It's a classic example of mission creep," said Jay Stanley, a senior policy analyst at the American Civil Liberties Union (ACLU) who reviewed the document at Hearst's request."Pretty soon we're going to have people walking through, you know, body scanners to go to a Little League game," Stanley said in an interview. "We don't want to turn America into an airport."The TSA declined a request for an interview about the program, as did Amtrak. America's largest passenger railroad also did not respond to a detailed list of questions about the soon-to-be-implemented screening of some of its passengers.The DHS document detailing the existence of the program states the new rail passenger screening will begin once Amtrak discloses it to passengers in its online privacy policy. At the time of this report, that webpage had not been updated since November. The data collected will be retained for two years, the document says. The biggest union of Amtrak employees, Transportation Communications International, urged the U.S. government to start screening rail passengers against Homeland Security's no-fly list after the January 6 attack on the U.S. Capitol by pro-Trump supporters. The union's statement also called for passengers whose names match the watchlist to be denied the ability to purchase Amtrak tickets.Khalid Turaani, who successfully challenged his inclusion on a watchlist, said he does "understand the security needs, without a doubt," for transportation security.However, his past experience with passenger watchlist screening prompted a warning to his fellow travelers: "There must be some transparency measures and I believe that is going to be key."WATCH NATIONAL INVESTIGATIVE UNIT COVERAGE OF RAIL SAFETY: 2018: Passenger railroads struggle to implement 'lifesaving' technology 2019: Amtrak failing to spot, stop impaired employees 2019: Delayed 'lifesaving' technology added to NTSB 'most wanted' 2020: After decades of delay, rail safety deadline nears 2022: Amtrak Asks TSA to Start Screening Rail Passengers Against Terrorist Watchlist for First TimeMark Albert is the chief national investigative correspondent for the Hearst Television National Investigative Unit, based in Washington D.C. April Chunko, Annie Klingenberg & Kevin Rothstein contributed to this report. Know of waste, fraud or abuse in government agencies? Have a confidential tip or inside information? Send information and documents to the National Investigative Unit at investigate@hearst.com.