USA Today WASHINGTON — Abdullah al-Kidd was arrested at a Dulles Airport ticket counter in March 2003, led away in handcuffs and sent to three different jails across the country. He says he was strip searched and subjected to humiliating conditions. After two weeks, he was released and never charged with a crime.

Al-Kidd, a U.S. citizen who is African-American and Muslim, later sued then-attorney general John Ashcroft and other officials for violating his rights. In a case now before the Supreme Court, he claims his arrest wrongly flowed from aggressive Justice Department policies after the Sept. 11, 2001, terrorist attacks.

The dispute tests when top officials can be held responsible for a policy that violates someone's rights. It is one of the lingering controversies surrounding Bush administration actions after 9/11, pitting national security concerns against civil liberties.

"It's one of the more visible cases this term," says University of Pennsylvania law professor Stephanos Bibas, who has written a "friend of the court" brief on behalf of legal history and criminal procedure professors. Their brief sides with al-Kidd and urges the justices to look deeply at the rights of detained witnesses through the centuries.

At the center of the case, which justices will hear March 2, is a longstanding federal law that allows "material witnesses" — people who might have significant information and be crucial to a case — to be held even though they are not suspected of wrongdoing. The law allows such individuals to be picked up if they might flee or elude a subpoena for testimony.

Al-Kidd says that after the 9/11 attacks, federal authorities distorted the material-witness law and used it to arrest suspects that the government lacked grounds to charge but wanted to investigate.

Fourth Amendment at issue

Al-Kidd was born in 1972 in Wichita and raised near Seattle. At the University of Idaho in the mid-1990s, he changed his name from Lavoni Kidd to Abdullah al-Kidd and converted to Islam.

When he was arrested in 2003, he said he was headed to Saudi Arabia for language and religious study. FBI agents picked him up on a material-witness warrant issued in the case of Sami Omar al-Hussayen, also of Idaho, who had been charged with visa fraud and making false statements. (Al-Hussayen was not convicted of those charges, and al-Kidd was never called to testify. During al-Kidd's time in jail, his lawyers say, he was interrogated about his own activities.)

Al-Kidd says the material-witness policy, which led to his "punitive, excessive and unlawful" 16-day detention, violated the Fourth Amendment rule that a person not be arrested without probable cause of wrongdoing.

"The Fourth Amendment does not permit locking up people just to investigate them," says Georgetown University law professor David Cole, who has tracked terrorism cases. "We are not seeing the kind of aggressive, systematic use of the material-witness statute as we did in the wake of Sept. 11, but what's at stake is ... the next time (the government) wants to ... use it for purposes never intended."

Five former attorneys general, all but one Republican appointees, have filed a "friend of the court" brief saying a lower-court decision that allowed al-Kidd's claim for damages to go forward — and is now on appeal to the justices — could discourage officials from effectively protecting national security.

Ashcroft had emphasized after 9/11 that the detention of material witnesses was vital to preventing attacks.

On al-Kidd's side, a group of 30 former federal prosecutors, spanning several past administrations, contends using the material-witness law to jail people for purpose of investigation violates rights.

"The material-witness statute provides prosecutors with an important law enforcement tool: the power to secure a witness's presence to testify in a criminal proceeding. It has no other legitimate purpose," they say.

Immunity is customary

The key question in the case before the justices is whether the attorney general can be held responsible for a policy that might violate constitutional protections.

Obama administration lawyers, defending Ashcroft, urge the justices to rule that the attorney general is shielded from lawsuits involving the witness law.

Justice Department attorneys note that prosecutorial duties are traditionally immune from lawsuits, and they reject arguments that officials' use of the law after the 9/11 attacks amounted to investigatory, rather than prosecutorial, work.

"To protect against vexatious litigation and harassment, absolute immunity protects prosecutors not just from liability but also from the burdens of defending a lawsuit," Neal Katyal, the acting U.S. solicitor general, tells the justices in his brief.

American Civil Liberties Union lawyer Lee Gelernt, representing al-Kidd, argues he should be able to vindicate his rights in court. Gelernt emphasizes that the Fourth Amendment allows people to be arrested only if authorities have grounds to believe a crime has been committed. "The material-witness statute represents a narrow exception to that general rule," he says, adding that it can be justified only to secure testimony, not conduct an investigation.

"Even after being released from detention, many material witnesses were subjected to restrictive release conditions — and yet still were never called to testify, as was the case with" al-Kidd, he tells the justices.

Fundamentally, Gelernt adds, "the material-witness statute was not enacted as a tool for preventive detention and investigation, and the Justice Department may not unilaterally turn it into one."