The attorney for Floyd Landis is questioning the accuracy of the positive testosterone tests attributed to the Tour de France winner and asking that doping charges be dismissed.

In a letter sent to the U.S. Anti-Doping Agency, attorney Howard Jacobs disputed the accuracy of the carbon isotope ratio tests performed on Landis' urine sample at a lab in France.

Jacobs also argued the analysis of a different test, the testosterone-epitestosterone analysis, "is replete with fundamental, gross errors," including mismatched sample code numbers. Jacobs said the positive finding on the backup 'B' sample came from a sample number not assigned to Landis.

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"It's incredibly sloppy" work, Jacobs said Monday in a telephone interview with The Associated Press. "It has to make you wonder about the accuracy of the work."

Both Landis and USADA had representatives at the testing of the 'B' sample.

USADA general counsel Travis Tygart said the doping agency couldn't comment on specific cases but noted it is not unusual for athletes and their attorneys to seek dismissal of cases.

"Our standard process allows all athletes to make a submission to the USADA review board, and those submissions are seriously considered prior to any case going forward," Tygart said.

A review board is expected to issue a recommendation on Landis' case sometime in the next week. That process could be delayed if USADA responds directly to Jacobs' letter.

If the review board recommends sanctions against Landis, he is expected to appeal and ask for an arbitration hearing. Jacobs has said he would seek a public hearing, and USADA has said it would agree to that.

Landis issued a statement reasserting his innocence.

"I did not take testosterone or any other performance-enhancing substance, and I'm very happy that the science is confirming my innocence," he said. "I was relieved, but not surprised, when I learned that scientific experts found problems with the test."

Dr. Gary Wadler, a member of the World Anti-Doping Agency and a spokesman for the American College of Sports Medicine, said Landis' attempt to have the charges dismissed by questioning the science behind the tests wasn't unusual.

"It's not useful to speculate about the science, until the science has had its day in the hearing process," Wadler said. "Only then do I think we can come to come conclusions. Until then, any assertion is only an assertion."

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