HUNTSVILLE, Texas (AP) - Defense lawyers have made a late request to halt the execution of a Texas woman set to become the first female put to death in the U.S. in three years.

The request was sent to a Dallas County judge Tuesday just hours before Kimberly McCarthy's scheduled execution.

University of Texas law professor Maurie Levin argues that McCarthy was the subject of racial discrimination by the jury of 11 whites and only one black that convicted her. McCarthy is black.

She said the same in a letter Friday to Dallas County District Attorney Craig Watkins.

Watkins' office calls the effort a "mere delay" tactic because the record doesn't support a valid legal claim for discrimination.

McCarthy faces execution in Huntsville for the 1997 beating, stabbing and robbing of a neighbor.

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