By Michael A. Verespej The U.S. Supreme Court has radically rewritten the definition of what constitutes employment discrimination in the workplace. In a landmark decision, the U.S. Supreme Court earlier this week unanimously ruled that an employee does not need to have direct evidence to prove that he or she has been a victim of age discrimination. The interpretation will likely be applied to other cases of alleged bias in the workplace based on sex, religion, race, or physical disabilities. In overturning an appellate court decision, the court reinstated an award of nearly $100,000 for Roger Reeves. Reeves had worked for toilet-seat manufacturer Sanderson Plumbing Products Inc. in Columbia, Miss., for 40 years until he was fired from his supervisor's job in 1995 for allegedly falsifying time records of other employees. The court said that an employee need not show direct evidence of discrimination if he or she could show that the stated reason for a dismissal lacks credibility. "Proof that the defendant's explanation is unworthy of credence is simply one form of circumstantial evidence that may be quite persuasive in showing that intentional discrimination occurred," said Justice Sandra Day O'Connor in writing the court's 19-page opinion. "In appropriate circumstances, the trier of fact can reasonably infer from the falsity of the explanation that the employer is [trying] to cover up a discriminatory purpose." The decision comes at a time when the number of employment discrimination cases are increasing dramatically. In 1998 there were more 21,000 employment discrimination cases filed in federal court. That's three times the number filed in 1990.