Laurie Tsao, a crackerjack card counter and one of the MIT students depicted in the book "Bringing Down the House," has a tough time plying her trade. Tsao, who also goes by her married name of Laurie Chang and several other monikers, is not welcome at casinos. In fact, according to a ruling Tuesday by the 9th Circuit Court of Appeals, Tsao has been tossed out of Desert Palace properties, including Caesar's Palace, at least five different times under four different names. Each time, she was warned that if she returned to any Desert Palace casino she could be arrested for trespassing.

After her last warning, in September 2007, Tsao received three promotional offers from the Caesar's marketing department, inviting her (under the name Laurie Tsao) to stay free at the hotel and to even bet on sports. Tsao would later assert that she regarded these invitations as an indication that the earlier trespass warnings had been rescinded. Nevertheless, when she returned to Caesar's in March 2008, she used an alias.

Despite the fake name, the casino identified Tsao as a so-called "advantage gambler" -- or card counter -- who had previously been given a trespass warning. Casino security guards approached her and demanded identification. Tsao said she didn't have any. After an argument, the guards grabbed her by the arm, handcuffed her and led her across the casino floor and into an interview room. The security chief called the Las Vegas police and, while waiting for an officer to arrive, began questioning Tsao about her identity. She gave him her married name, Laurie Chang. When a Las Vegas police officer showed up, she told him the same thing. But he rummaged through Tsao's pocketbook until he found a set of car keys. Using the panic button on her key chain, he located her car and determined that her name in the motor vehicle registry was Tsao, not Chang. Even though Tsao's lawyer, noted gamblers' counsel Robert Nersesian of Nersesian & Sankiewicz, arrived on the scene, the casino security guard issued her a summons for trespassing and the Las Vegas officer took her to the local jail on charges of impeding an investigation.

Both charges were subsequently dropped by prosecutors, after which Tsao brought her own civil case against the casino and the Las Vegas police officer, asserting federal unreasonable seizure claims and state-law battery, false imprisonment, assault and defamation claims. U.S. District Judge Robert Jones of Las Vegas granted the defendants summary judgment on all of Tsao's claims, finding that both the casino and the Las Vegas police had probable cause to arrest Tsao.

A three-judge 9th Circuit panel ruled Tuesday that the issue is quite a bit more complicated than that. And though the panel -- Chief Judge Alex Kozinski and Judges Stephen Reinhardt and Marsha Berzon -- ended up affirming the summary judgment grant on Tsao's constitutional claim, the 9th Circuit's reasoning leaves the door open for other gamblers to bring unreasonable seizure suits against Las Vegas casinos.

To be open to those constitutional claims, wrote Berzon in the 9th Circuit's opinion, gamblers would have to show that casinos operate in tandem with the state when they arrest gamblers and issue them summonses for the misdemeanor crime of trespassing. Private security guards aren't normally empowered to issue criminal citations, but the appellate judges explained in the Tsao ruling that the Las Vegas police, to ease demands on its officers, offer a course for casino enforcers. When casino guards have completed the course, they can issue criminal summonses for trespassing (subject to certain restrictions). Those facts, the 9th Circuit said, make Las Vegas casinos state actors, thus subjecting them to liability for unconstitutional search and seizure.

The 9th Circuit's finding aligns the court with the 6th Circuit, which found that a Michigan casino that also used private security guards empowered to make arrests, was liable for unconstitutional seizure in a 2005 case called Romanski v. Detroit Entertainment. The Nevada Supreme Court has also held that casinos are not immune from such suits, in a 2009 decision called Grosjean v. Imperial Palace. (The gambler in that case, James Grosjean, was represented by Tsao's lawyer, Nersesian.)

For Tsao, the 9th Circuit holding that Caesar's can be liable for the federal claim wasn't enough to prevail. The court said that to show her search was unconstitutional, she would have to prove that Caesar's had an official policy that made her particular arrest by casino guards unreasonable. Tsao pointed to the invitations she had received from Caesar's as evidence that she could not have expected to be seized. The 9th Circuit held that the apparent gap in communication between Caesar's security and marketing departments doesn't amount to a policy.

It also, however, revived Tsao's common-law claims against the casino, finding that they rest on a determination of the casino's probable cause, which, in turn, rests on a state-law interpretation of whether the promotion invitations Tsao received from the casino rescinded the previous trespass warnings. It's not clear if the federal court would retain jurisdiction, given that the 9th Circuit wiped out Tsao's federal claims. Tsao counsel Nersesian told me he's considering whether to request a rehearing or an en banc hearing of the dismissal of Tsao's constitutional claims.

Caesar's counsel Thomas Dillard of Olson, Cannon, Gormley & Desruisseaux didn't return a call for comment.

(Reporting by Alison Frankel)

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