The Murder of David Harris - Clara Harris

On July 24, 2002, Clara Harris confronted her husband of 20 years about the affair he was having with his former receptionist. She did this in the foyer of the hotel he and his mistress had gotten a room in in Houston, Texas. When told to take it outside, Clara got behind the wheel of her car and proceeded to run him over and kill him.
Sources for this episode:
Wikipedia - Friendswood, Texas, Houston, List of people from Houston, A. J. Foyt, Murder of David Lynn Harris, Mountain View Unit
ABC News - Woman Who Ran Over Husband Tells Of Marriage
KHOU 11 - Clara Harris being released in May, 15 years after running over cheating husband
ABC 13 - Clara Harris: Wife Who Fatally Ran Over Cheating Husband
CBS News - Mistress: He Said Marriage Was 'Open'
Oprah - Shattered Lives
Texas Monthly - Suburban Madness