On July 23, 2008 it was reported that Jessica Hardy had tested positive for clenbuterol. Her attorney confirmed on July 24th that Hardy's "A" and "B" samples from a test administered on July 4th were positive for clenbuterol, a banned stimulant. It has been noted that the positive test was sandwiched by two negative tests, each within a few days of the positive result.
On August 1, 2008, the USADA released a statement stating "The U.S. Anti-Doping Agency (USADA) announced today that U.S. Swimmer, Jessica Hardy, of Long Beach, CA, tested positive for the prohibited substance clenbuterol at the U.S. Olympic Trials on July 4, 2008, and has agreed to withdraw from the 2008 United States Olympic Team in the best interests of the team.
| Event | Short course | |
|---|---|---|
| 50 m breaststroke | 29.58 (WR) | |
| 100 m breaststroke | 1.04.22 | |
| (WR) – World record | ||