His first term was marked by SEDCO's involvement in the then largest oil blowout in history, the Ixtoc I oil spill, which caused extensive environmental damage. Charlie Brooks, Jr., became the first prisoner to be executed by lethal injection (December 1982). Clements faced heavily Democratic state legislatures. In 1980, Clements changed the death penalty for Randall Dale Adams to life in prison. Adams was the subject of "The Thin Blue Line", an Errol Morris documentary movie. Adams was found to be innocent in 1989 after serving twelve years in prison.