Can defendants challenge jury instructions they failed to preserve at trial? State v. Cox Explained

The Utah Court of Appeals addressed important issues regarding preservation of error and ineffective assistance of counsel claims in State v. Cox, a case involving convictions for aggravated sexual abuse of a child.

Background and Facts

Cox lived with his girlfriend and her daughter S.W. from 1994 to 1997, first as an adult cohabitant and later as her stepfather after marrying the mother in 1996. During this period, Cox repeatedly sexually abused S.W., who was between six and nine years old. Cox was convicted of multiple counts of aggravated sexual abuse, sodomy, and rape of a child, all first-degree felonies.

Key Legal Issues

Cox raised three main arguments on appeal: (1) his convictions were based on an ex post facto law because the jury instruction improperly defined his “position of special trust” using statutory language that wasn’t in effect during the charged period; (2) the state improperly prosecuted him in Salt Lake County for abuse that occurred in Wasatch County; and (3) evidence of abuse in Wasatch County violated Rule 404(b). None of these issues were preserved at trial.

Court’s Analysis and Holding

The court rejected Cox’s plain error challenge to the jury instruction because defense counsel had affirmatively stated he had no objections to the instructions. This invited any error and precluded plain error review. On the ineffective assistance claim, while the court found counsel’s performance deficient for failing to object to the problematic instruction, Cox could not show prejudice because overwhelming evidence supported his convictions under the proper statutory provisions applicable during the charged period. The court also rejected his venue and Rule 404(b) challenges, finding he was only prosecuted for Salt Lake County offenses and that evidence of the pattern of abuse was properly admissible.

Practice Implications

This case demonstrates the critical importance of preserving objections at trial. Even constitutional challenges like ex post facto violations cannot be reviewed under the plain error doctrine when counsel affirmatively waives objection. For ineffective assistance claims, practitioners must remember that both deficient performance and prejudice must be established—overwhelming evidence supporting convictions under alternative theories can defeat prejudice arguments even when counsel’s performance was clearly deficient.