Louisiana Sen. David Vitter may be called to testify on behalf of a woman accused of running an upscale Washington prostitution service, attorneys said Monday at the opening of trial. The Republican senator was among several possible witnesses identified Monday in the racketeering and money laundering case against Deborah Palfrey. Among others on the list is Harlan Ullman, a military strategist who created the concept of "shock and awe" that the United States used to open hostilities against Iraq (web|news) more than five years ago. Prosecutors said they planned to call about a dozen former escorts and several clients.

Vitter, a Republican senator in his first term, has acknowledged being involved with Palfrey's escort service. But after issuing brief statements apologizing for "a very serious sin," he has ducked follow-up questions. At trial, he would not have that luxury.

Prosecutor Catherine K. Connelly called the witness box "maybe the hottest seat in D.C. this year." Attorneys for both sides told jurors they would see former clients discussing embarrassing and sometimes graphic details about their personal lives.

"It gives me no great pleasure to walk these people through these situations," Palfrey's attorney, Preston Burton, told jurors during opening statements.

Burton told jurors that Palfrey ran a high-class fantasy business. Clients called in looking for a date, he said, and Palfrey got paid whether they played cards, saw a movie or - in the case of a few women who chose to - had sex. The escorts signed a contract promising not to break the law, he said, and the clientele was made of up "educated people who know when they're crossing the line."

Vitter's lawyer did not return a message seeking comment Monday. The senator was elected in 2004 after representing Louisiana's 1st Congressional District in the House from 1999 to 2004. Vitter and his wife Wendy have four children.

Burton also named Randall Tobias, a former senior State Department official, as a possible witness. Tobias resigned his post last year after phone records linked him to the escort service. Burton did not say what he expected the witnesses to say, but a previous attorney has said he wanted to make Vitter reveal exactly what services Palfrey's company provided the senator.

If called to the stand, he could refuse to testify, citing his constitutional right not to incriminate himself. But that still would require an embarrassing trip to court, followed by a discussion of whether the Justice Department would promise not to prosecute him for anything he discussed.

Prosecutors listed among their witnesses several former escorts as well as military strategist Ullman, the "shock and awe" war strategist.

Palfrey says Ullman was a regular client. Ullman has declined to discuss what he has called "outrageous allegations."

Connelly said that when clients called the escort service, Pamela Martin and Associates, they spoke to Palfrey in California. She arranged dates from there, prosecutors said, and required escorts to mail her money orders with her percentage of the fees.

"You're going to hear from men who paid thousands and thousands of dollars" on escorts and women who sold sex for about half of a $250 fee, Connelly said. "Rest assured that very few of these people want to come forward and testify in this case."