Peterson's attorney said during opening statements, "the fact that there's no eyewitness and there's no smoking gun... no DNA." Peterson is accused of killing his third wife, Kathleen Savio. His lawyer went on to say Savio's death is the result of hitting her head after slipping in the bathroom.
But, prosecutors portrayed a violent Peterson telling the jury he grabbed Savio by the neck and said "I could kill you and no one would know."
Legal experts say the trial could take up to a month to finish.