Nicholas George, a former college student who was detained at an airport for five hours after Transportation Security Administration (TSA) agents found him carrying Arabic language flashcards, had his bid to sue the federal agents rejected by the 3rd U.S. Circuit Court of Appeals on Tuesday.

According to the Associated Press, with the help of the American Liberties Union (ACLU), George wanted to sue three TSA agents and two FBI agents for stopping him at Philadelphia International Airport in August 2009, claiming they violated his free speech rights and conducted improper search and arrest based on the flashcards. He was also carrying a book critical of American policy in the Middle East.

George was catching a flight from Philadelphia to Pomona College in California, where he was studying Arabic, when TSA agents saw the words “bomb and “terrorist” written on his flashcards and called police.

Writing for the panel of three judges, Chief Judge Theodore McKee, said George had the right to carry and use the flashcards and book and called the detention by the TSA officials “at the outer boundary” of constitutional protections against absurd search and seizure, but said the agents were justified in bringing George in for questioning.

"It is simply not reasonable to require TSA officials to turn a blind eye to someone trying to board an airplane carrying Arabic-English flashcards with words such as "bomb," ''to kill," etc.," he wrote. "Rather, basic common sense would allow those officials to take reasonable and minimally intrusive steps to inquire into the potential passenger's motivations.”

“Suspicion remained, and that suspicion was objectively reasonable given the realities and perils of air passenger safety,” the decision reads. “In a world where air passenger safety must contend with such nuanced threats as attempts to convert underwear into bombs and shoes into incendiary devices, we think that the brief detention that followed the initial administrative search of George was reasonable.”

The ACLU explained on its website that George, who was majoring in Physics, “had recently completed a study abroad program in Jordan, was using the cards to aid his Arabic language studies.”

ACLU attorney Benjamin Wizner told the AP that the decision was perplexing.

“Were they saying that he needed those flash cards to try to hijack the plane in Arabic? Because he presumably knew how to do that in English,” Wizner said.

Wizner said the decision could be appealed to the full 3rd Circuit or to the U.S. Supreme Court, and that it didn’t affect pending legal action against Philadelphia police or the government.