Can Utah prosecute homicide charges for killing an unborn child? State v. MacGuire Explained

In State v. MacGuire, the Utah Supreme Court addressed whether the state’s criminal homicide statute could constitutionally include “unborn child” within its definition of human beings for prosecution purposes. The case arose when defendant Roger Martin MacGuire was charged with two counts of aggravated murder for allegedly killing his pregnant ex-wife and her unborn child.

Background and Facts

MacGuire allegedly shot his ex-wife four times at her workplace after learning she was engaged and pregnant. One bullet severed the umbilical cord and traveled through the placenta and unborn child, which the medical examiner estimated was between thirteen and fifteen weeks gestational age. MacGuire was charged with aggravated murder for both deaths, with the state arguing that killing two persons during the same criminal episode constituted an aggravating circumstance.

Key Legal Issues

MacGuire challenged the charges on two grounds: first, that the term “unborn child” in the criminal homicide statute was unconstitutionally vague both facially and as applied; and second, that the criminal homicide and aggravated murder statutes violated equal protection guarantees because physicians performing abortions and researchers destroying embryos were not similarly prosecuted.

Court’s Analysis and Holding

The court applied the standard for void for vagueness challenges, requiring that statutes provide adequate notice of prohibited conduct and not encourage arbitrary enforcement. Using a correctness standard of review, the court found that “unborn child” has a clear commonsense meaning encompassing “an individual human life in existence and developing prior to birth.” The court noted that other sections of Utah’s criminal code used the term consistently, referring to development “from fertilization to full term.”

The court declined to address the equal protection challenge because MacGuire failed to petition for interlocutory review of that specific issue, despite raising it in his motion to dismiss.

Practice Implications

This decision establishes that Utah’s criminal homicide statute can constitutionally encompass the killing of unborn children at any stage of development. The court’s analysis demonstrates the heavy burden challengers face when attacking legislative enactments as unconstitutional, particularly when statutory terms have commonsense meanings. The case also highlights the importance of properly preserving issues for interlocutory appeal—constitutional challenges not included in the petition for permission to appeal will not be addressed even if mentioned in district court filings.