Some of the actions taken as a result of the threat levels have been challenged as being illegal under the U.S. Constitution 's Fourth Amendment . For example , in November 2002 , the city of Columbus , Georgia forced all people wishing to protest at the School of the Americas to first submit to a metal detector search . The advocacy group School of the Americas Watch asked a federal trial court to enjoin the mass searches , but the court refused and simply dismissed the complaint . When the protestors appealed , the city justified the metal detector searches in part because of the " yellow " threat level . However , the U.S. Court of Appeals for the Eleventh Circuit found that this was merely a '' post hoc '' justification for the searches , because the city had not even mentioned the terror alert system in its arguments at the trial court level . Even if the city did in fact rely on the alert system at the time it acted , said the court , We ... reject the notion that the Department of Homeland Security 's threat advisory level somehow justifies these searches . Although the threat level was " elevated " at the time of the protest , " t o date , the threat level has stood at yellow ( elevated ) for the majority of its time in existence . It has been raised to orange ( high ) six times . " Given that we have been on " yellow alert " for over two and a half years now , we can not consider this a particularly exceptional condition that warrants curtailment of constitutional rights . We can not simply suspend or restrict civil liberties until the War on Terror is over , because the War on Terror is unlikely ever to be truly over . September 11 , 2001 , already a day of immeasurable tragedy , can not be the day liberty perished in this country . Furthermore , a system that gave the federal government the power to determine the range of constitutionally permissible searches simply by raising or lowering the nation 's threat advisory system would allow the restrictions of the Fourth Amendment to be circumvented too easily . Consequently , the " elevated " alert status does not aid the City 's case . '' Bourgeois v. Peters '' , 387 F. 3d 1303 , 1312 ( 11th Cir . 2004 ) Incidentally , this was also the first time that Wikipedia was quoted in a published decision of a federal appeals court
immeasurable tragedy
September 11 attacks
Homeland Security Advisory System