In order to obtain a “extreme emotional disturbance” in connection with the statutory defense to the crime of murder the defendant must show: “(1) when he has no mental illness as defined in section 76–2–305 (insanity or diminished capacity); and (2) when he is exposed to extremely unusual and overwhelming stress; and (3) when the average reasonable person under that stress would have an extreme emotional reaction to it, as a result of which he would experience a loss of self-control and that person's reason would be overborne by intense feelings, such as passion, anger, distress, grief, excessive agitation, or other similar emotions.”State v. Lambdin, 2017 UT 46, ¶ 15, 424 P.3d 117, 121, holding modified by State v. Sanchez, 2018 UT 31, ¶ 15, 422 P.3d 866.
In this case, the Defendant and his wife were in a rocky marriage. A month before he murdered her, she had asked for a divorce. He also discovered she was having an extra-marital affair and was pregnant with another man’s child. A month later, the Defendant killed his wife. The Defendant sought to reduce the level of his offense to manslaughter by proving special mitigation by extreme emotional distress by urging the Court formulate a new definition of extreme emotional distress. The Defendant also argued, in the alternative, that the current definition of extreme emotional distress did not require the defendant to show that his loss of self-control was reasonable. The Court ruled against him on both arguments holding that the definition was correct and that the Defendant defendants to prove that they were “exposed to extremely unusual and overwhelming stress,” and that “the average reasonable person under that stress would have an extreme emotional reaction to it, as a result of which he would experience a loss of self-control and that person's reason would be overborne by intense feelings.”