David Kelley is an American television writer, producer, and former attorney, known as the creator of Doogie Howser, M.D., Picket Fences, Chicago Hope, The Practice, Ally McBeal, Boston Public, Boston Legal, Harry's Law, Goliath, Big Little Lies, Mr. Mercedes, Big Sky, and Nine Perfect Strangers as well as several films. Kelley is one of very few screenwriters to have created shows that have aired on all four top commercial U.S. television networks (ABC, CBS, Fox, and NBC).