Embattled Tour de France champion Floyd Landis's father-in-law David Witt has been found dead in San Diego, California, after committing suicide in his car.

David Witt's body was discovered at a parking garage Tuesday afternoon according to the San Diego County Medical Examiner's office. He had a gunshot wound to the head, and his death was ruled a suicide.

Witt was the stepfather of Landis's wife Amber, and was at the finish line when the American won this year's Tour de France cycling race. Witt and Landis served as best man at each other's weddings, and Witt was an avid amateur cyclist.

Landis has been under investigation after testing positive for testosterone during the Tour de France last month. The 30-year-old cyclist has cited several reasons for his positive test, including cortisone shots for an arthritic hip and thyroid medication. He is appealing his test, but the Tour de France has said it no longer considers him the champion.