WASHINGTON, D.C.: Questions about possible civil liberties violations have been raised by a White House suggestion that airport security officers closely watch passengers -- and pay special attention to their baggage -- if they fit certain “red flag” characteristics typical of known hijackers and terrorists. The proposal, part of a new series of recommendations from a White House aviation safety commission, also suggests that airlines should take steps to make sure that such passengers actually board the flights on which they’ve checked baggage. Despite language in the report stipulating that such profiles not be based on race, ethnicity or gender, civil libertarians fear that people of Middle Eastern origin in particular will be singled out. "The proposed profiling system is invasive of privacy and likely to be discriminatory," said American Civil Liberties Union lawyer Gregory Nojeim. He argued that airlines can only prevent a terrorist from checking a bomb and then skipping the flight by matching every bag to its owner: "The airlines have prevailed on this commission not to go to full luggage match because they don't want to pay for it." Maybe so, but passengers are also likely to rebel when such a system produces even more delays, long lines and requirements for early airport arrivals. While the Presidential panel noted that U.S. Customs, using its own profiling system, has been able to increase drug seizures while stopping fewer people, the analogy is not perfect. After all, taking a flight from Chicago to San Francisco should not be as complicated as entering the country.