from employing his own expert witness and he did not indicate any desire to do so. Therefore, we conclude Lagerev fails to demonstrate that the district court abused its discretion by allowing the State's expert rebuttal witness to testify. See Lopez v. State, 105 Nev. 68, 81, 769 P.2d 1276, 1285 (1989). Lagerev next contends that the district court erred by declining to allow him to call an untimely disclosed impeachment witness because impeachment witnesses need not be disclosed prior to trial and the witness' testimony directly supported his theory of defense. Lagerev informed the district court that the witness would impeach the testimony of a Highway Patrol officer. On appeal, Lagerev contends that the witness' testimony was admissible to impeach the testimony of a different witness. Because Lagerev did not offer the testimony for this purpose in the district court, we decline to consider this contention on appeal. See McCall v. State, 97 Nev. 514, 516, 634 P.2d 1210, 1212 (1981) ("Where evidence is not offered for a particular purpose at trial, an appellate court will not consider it for that purpose on appeal."). Moreover, even if the district court abused its discretion by concluding that the proffered witness could not testify in Lagerev's case-in-chief due to untimely disclosure, see NRS 174.234(1)(a)(1); Mitchell v. State, 124 Nev. 807, 819, 192 P.3d 721, 729 (2008), any error was harmless because the witness' proffered testimony related only to a prior existing condition and was thus irrelevant to the determination of Lagerev's guilt. See NRS 484C.430(1); Williams v. State, 118 Nev. 536, 550-51, 50 P.3d 1116, 1125-26 (2002) (concluding that evidence of county's negligence was irrelevant in a trial for DUI causing death because any negligence was a preexisting condition that could not establish that defendant was not the proximate cause of the

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EEER ..q:ItEz-2 .S1141111:•1 accident); Etcheverry v. State, 107 Nev. 782, 784-85, 821 P.2d 350, 351-52 (1991) (discussing proximate cause in context of DUI prosecution); see also Bostic v. State, 104 Nev. 367, 369-70, 760 P.2d 1241, 1243 (1988). Lagerev also asserts that the prosecutor made an incorrect statement of law during closing argument and the district court erred by declining to dismiss the entire jury because it was "tainted" during the voir dire process. Lagerev does not support these contentions with any cogent argument or citation to authority and we therefore decline to address them. See Maresca v. State, 103 Nev. 669, 673, 748 P.2d 3, 6 (1987). Accordingly, we ORDER the judgment of conviction AFFIRMED.

A-4in Hardesty

P-arraguirre U Cherry

cc: Hon. Jessie Elizabeth Walsh, District Judge Sandra L. Stewart Attorney General/Carson City Clark County District Attorney Eighth District Court Clerk

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