Security at Logan International Airport, praised for its overhaul after Sept. 11, 2001, has come under fire for a technique that allows police to stop and question people they believe are behaving suspiciously. The American Civil Liberties Union filed a lawsuit Wednesday challenging the “behavior pattern recognition” program at Logan — where two planes were hijacked and crashed into the World Trade Center — saying it “effectively condones and encourages” racial and ethnic profiling. The lawsuit was filed on behalf of King Downing, the ACLU’s national coordinator for racial profiling, who alleged he was harassed by state police last year. It seeks unspecified monetary damages, and asks the court to declare the screening system unconstitutional. Full Story