By JENNA FRYER AP Auto Racing Writer

Jeremy Mayfield tested positive again for methamphetamine, NASCAR said, igniting another round of denials from the driver, who angrily accused the sanctioning body of paying his stepmother to lie about his alleged past drug use.

The positive result from a July 6 random test was included in a U.S. District Court filing Wednesday that asked the federal judge who lifted Mayfield's drug suspension to reinstate the ban. The filing included an affidavit from Mayfield's stepmother, Lisa, who said she witnessed the driver using methamphetamine at least 30 times over seven years.

"I don't trust anything NASCAR does, anything Dr. David Black does, never have, never will," Mayfield told The Associated Press in a phone interview. Black is the administrator for NASCAR's drug-testing program.

"And they picked the wrong woman to use against me because that (expletive) is trash and has got nothing on me but lies."

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