Updated

Seven years ago, Russian courts convicted a wealthy American motel owner of molesting children, sent him to prison, then expelled him from the country.

The experience did little to keep Anthony "Mark" Bianchi stateside. Over the next few years, U.S. officials allege, he traveled to Moldova, Romania, Cambodia and Cuba to recruit destitute boys for sexual trysts.

Bianchi, 44, of North Wildwood, N.J., faces trial beginning Monday under a controversial federal law aimed at thwarting "sex tourism." He is accused in this country of committing crimes — assaulting nearly a dozen minors — on foreign soil.

More than 50 cases have been brought under what's known as the Protect Act, and more than 30 of the defendants have been convicted, the Justice Department says.

So far, however, only one federal appeals court — the 9th U.S. Circuit Court of Appeals — has reviewed the law, upholding it in a 2-1 ruling. The U.S. Supreme Court decided not to hear an appeal of that decision.

Critics, including dissenting 9th U.S. Circuit Judge Warren J. Ferguson, charge that Congress reached too far in giving international police power to U.S. prosecutors. Ferguson asked if U.S. agents should likewise round up Americans who buy marijuana in Amsterdam or Cuban cigars in Timbuktu.

"It is a very unusual theory to say that you can prosecute an American citizen in this country for actions taken completely in another country," said Rory Little, a former federal prosecutor and Justice Department official who is now a University of California law professor. "This is not a crime against America, although it's a crime against universal morality."

The majority in the 9th Circuit case found the law to be an appropriate extension of the Constitution's foreign commerce clause, since money changed hands.

The 9th Circuit case involved Michael L. Clark, a 70-year-old Seattle man who in 2004 became the first person prosecuted under the law. He pleaded guilty to molesting boys in Cambodia, while reserving the right to challenge the law itself, and is serving a 97-month sentence.

Beyond the constitutional issues, attorneys say defending clients in these cases is a nightmare, in part because they can't match the overseas investigative resources, including diplomatic and political clout, of the U.S. government.

"To do this in a foreign country, you have to send an investigator over there, and that person has to make contacts in the community. That may not be possible, given the language differences and cultural differences," said Michael Filipovic, an assistant federal public defender in Seattle.

In the case due to start Monday, prosecutors charge that Bianchi assaulted nearly a dozen teenagers and plied them with money, liquor, gifts and trips.

"Americans go to these countries and create a pretty bad image," Assistant U.S. Attorney Michael Levy said. "A hundred dollars can buy a lot of food for a pretty long time for a lot of these families. ... This is the kind of case that shows why there's a need for this (law)."

Bianchi's lawyer, Mark Geragos, said the discovery process has shown what defense attorneys are up against in such cases. He said records make it difficult to even verify the age of the reported victims, and he planned to argue that several of the boys recanted their accusations.