Chicago — There was the fallout from BALCO. Then, Olympic medal-winners who've later failed drug tests. Now, there is an ongoing investigation that may further soil the reputations of elite athletes. It would seem the last thing the United States Olympic Committee should do is shout from the mountaintops, "We are clean."

But that's what happened Tuesday.

U.S. Olympic officials expressed confidence that increased drug testing and other measures — which they wouldn't disclose — will ensure the American team will avoid positive tests and embarrassment in Beijing this summer.

"[With] the changes we've made to our doping programs, the protocols we've had in place, we're very confident that this team is clean and we'll field a clean team in Beijing," said Jim Scherr, the USOC's CEO. "Of course there's no way we can guarantee anything. But we feel very good about this team and the progress we've made [against] doping."

USOC chairman Peter Ueberroth also said, "This will be a clean team," adding that athletes "have seen the penalties [for positive tests], whether it's dignity lost or jail time." He also alluded to deterrents, but said: "The exact steps we're taking is something we're not going to talk about."

Ueberroth said he was "pleased" about the relatively few positive tests at the 2004 Olympics in Athens and the World Championships in 2006. The timing was odd, however, given the impending federal drug trial of former track coach Trevor Graham, whose long list of shamed athletes include Marion Jones.

Graham has been charged with three counts of perjury. The New York Times reported last week that one of the government's witnesses against Graham will identify two dozen athletes whom Graham helped supply performance-enhancing drugs to, including 12 who have won a total of 26 Olympic medals and 21 World Championships.