- 856 - N ebraska S upreme C ourt A dva nc e S heets 301 N ebraska R eports
STATE v . TUCKER
Cite as 301 Neb. 856

S tate of N ebraska , appellee , v

. C arlos A

. T u c ker , appella n t

. ___ N.W.2d ___

Filed December 14, 2018. No. S-17-926.

1. Rules of Evidence: Appeal and Error. An appellate court reviews for abuse of discretion a trial court’s evidentiary rulings on relevance, whether the probative value of evidence is substantially outweighed by the danger of unfair prejudice, and the sufficiency of a party’s founda

tion for admitting evidence. 2. Expert Witnesses: Appeal and Error. The standard for reviewing the admissibility of expert testimony is abuse of discretion. 3. Convictions: Evidence: Appeal and Error. In reviewing a criminal conviction for a sufficiency of the evidence claim, whether the evidence is direct, circumstantial, or a combination thereof, the standard is the same: An appellate court does not resolve conflicts in the evidence, pass on the credibility of witnesses, or reweigh the evidence; such matters are for the finder of fact. The relevant question for an appellate court is whether, after viewing the evidence in the light most favorable to the prosecution, any rational trier of fact could have found the essential ele

ments of the crime beyond a reasonable doubt. 4. Sentences: Appeal and Error. An appellate court will not disturb a sen

tence imposed within the statutory limits absent an abuse of discretion by the trial court. 5. Evidence: Words and Phrases. Evidence is relevant if it tends in any degree to alter the probability of a material fact. 6. Rules of Evidence. Under Neb. Evid. R. 403, Neb. Rev. Stat. § 27-403 (Reissue 2016), relevant evidence may be excluded if its probative value is substantially outweighed by the danger of unfair prejudice. 7. Evidence. Most, if not all, evidence offered by a party is calculated to be prejudicial to the opposing party. 8. Evidence: Words and Phrases. Unfair prejudice means an undue tend

ency to suggest a decision based on an improper basis. Nebraska Supreme Court Online Library www.nebraska.gov/apps-courts-epub/ 02/15/2019 08:06 AM CST- 857 - N ebraska S upreme C ourt A dva nc e S heets 301 N ebraska R eports
STATE v . TUCKER
Cite as 301 Neb. 856

9. ____: ____. Unfair prejudice speaks to the capacity of some concededly relevant evidence to lure the fact finder into declaring guilt on a ground different from proof specific to the offense charged, commonly on an emotional basis. 10. Witnesses: Juries: Appeal and Error. The credibility and weight of witness testimony are for the jury to determine, and witness credibility is not to be reassessed on appellate review. 11. Sentences: Appeal and Error. Where a sentence imposed within the statutory limits is alleged on appeal to be excessive, the appellate court must determine whether a sentencing court abused its discretion in con

sidering and applying the relevant factors as well as any applicable legal principles in determining the sentence to be imposed. 12. Sentences. In determining a sentence to be imposed, relevant factors customarily considered and applied are the defendant’s (1) age, (2) men

tality, (3) education and experience, (4) social and cultural background, (5) past criminal record or record of law-abiding conduct, and (6) moti

vation for the offense, as well as (7) the nature of the offense and (8) the amount of violence involved in the commission of the crime. 13. ____. The appropriateness of a sentence is necessarily a subjective judg

ment and includes the sentencing judge’s observation of the defendant’s demeanor and attitude and all the facts and circumstances surrounding the defendant’s life. 14. ____. Generally, it is within a trial court’s discretion to direct that sentences imposed for separate crimes be served either concurrently or consecutively.
Appeal from the District Court for Lancaster County: D arla S . I deus , Judge. Affirmed.
Joseph D. Nigro, Lancaster County Public Defender, and John C. Jorgensen for appellant.
Douglas J. Peterson, Attorney General, Erin E. Tangeman, and, on brief, Sarah E. Marfisi for appellee.

H eav ic a n , C.J., C assel , S ta c y , F u n ke , P ap i k , and F reude n berg , JJ.

P

ap i k , J. Carlos A. Tucker appeals his convictions and sentences for one count of first degree sexual assault of a child and two- 858 - N ebraska S upreme C ourt A dva nc e S heets 301 N ebraska R eports
STATE v . TUCKER
Cite as 301 Neb. 856
counts of incest, related to an incident with his girlfriend’s children. Evidence at trial showed that Tucker engaged in sex acts with M.T., age 11, and that M.T. and her two broth

ers, E.T., age 12, and R.T., age 10, engaged in sex acts upon Tucker’s instructions. The main issue presented by this appeal is whether the district court abused its discretion in admitting “Y-STR” DNA evidence over Tucker’s objections. We con

clude that it did not. We further reject Tucker’s contentions that the evidence was insufficient to support his convictions and that the district court imposed excessive sentences. Finding no error, we affirm.

BACKGROUND Charges Against Tucker. The State charged Tucker with one count of first degree sexual assault of a child in violation of Neb. Rev. Stat. § 28-319.01(2) (Reissue 2016) and two counts of incest with a person under 18 years of age in violation of Neb. Rev. Stat. § 28-703 (Reissue 2008). The charges arose out of allegations by M.T., E.T., and R.T. that Tucker, their mother’s live-in boyfriend, had engaged in sex acts with M.T. and that M.T. had engaged in sex acts with E.T. and R.T. after being instructed to do so by Tucker.
Pretrial Proceedings. Prior to trial, Tucker filed a motion in limine seeking to exclude all evidence of Y-STR DNA testing pursuant to Daubert v. Merrell Dow Pharmaceuticals, Inc. , 509 U.S. 579, 113 S. Ct. 2786, 125 L. Ed. 2d 469 (1993), and Schafersman v. Agland Coop , 262 Neb. 215, 631 N.W.2d 862 (2001) ( Daubert / Schafersman ). He also alleged that such evidence would con

fuse the jury and that its prejudicial effect would outweigh its probative value. At a pretrial hearing on the motion, the district court heard expert testimony by Shannen Bishop, a DNA analyst at the University of Nebraska Medical Center (UNMC). Bishop testi

fied concerning the Y-STR DNA analysis she conducted on- 859 - N ebraska S upreme C ourt A dva nc e S heets 301 N ebraska R eports
STATE v . TUCKER
Cite as 301 Neb. 856

DNA found on the interior of the shorts M.T. wore on the day of the alleged assault. Bishop also explained the origins, mechanics, and limitations of Y-STR DNA testing, as well as the extent to which it is accepted in the scientific community. Bishop testified that Y-STR DNA testing looks only at the male chromosome portion of DNA, while autosomal DNA testing looks at all 23 chromosomes inherited by each person. She dismissed as irrelevant several journal articles submitted by Tucker purporting to discredit the application of Y-STR DNA testing to small ethnic populations. Bishop explained that the articles examined very small, specific sample sizes and that Y-STR DNA science has improved since the articles were pub

lished in the early 2000’s. She further pointed out that the U.S. Y-STR database, which she used in her analysis, was not even established when most of the articles were written. Following the hearing, the district court denied Tucker’s motion in limine. It applied the Daubert / Schafersman analyti

cal framework and determined the reasoning and methodology behind Bishop’s opinions and Y-STR DNA testing to be valid and reliable. The district court further rejected Tucker’s argu

ment that the prejudicial effect of Y-STR DNA evidence out

weighed its probative value.

Evidence at Trial. At the jury trial, M.T., E.T., and R.T. testified that on the day at issue, their mother was at work and Tucker was home with them. The children testified that Tucker, then age 31, invited them to play a series of games in which he would give the winner candy. The games began innocuously enough with the children competing to be the last to laugh, but they progressed to include the children undressing. In one game, the children undressed and Tucker hid their clothes. In another, Tucker instructed the children to switch clothing with one another. The children testified that after a series of these games, Tucker directed them to the living room. Tucker instructed the children to disrobe completely, and he played pornography- 860 - N ebraska S upreme C ourt A dva nc e S heets 301 N ebraska R eports
STATE v . TUCKER
Cite as 301 Neb. 856
on the television. The boys testified that Tucker told them to masturbate. All three children testified that at some point while they were in the living room, Tucker licked M.T.’s vagina, and E.T. and R.T. testified that they followed Tucker’s instructions to do the same. The three children testified that Tucker also directed M.T. to put her mouth on his penis while, M.T. testi

fied, he used his hand to move her head. All three children also testified that M.T. complied with Tucker’s instructions to put her mouth on E.T.’s and R.T.’s penises as well, with R.T. speci

fying that M.T. “suck[ed]” on their penises. There was also testimony that Tucker placed an electric toothbrush on M.T.’s vagina. The children testified that they saw “white stuff” or “clear stuff” come out of Tucker’s penis, which he wiped off with a tissue or napkin. R.T. observed some of the fluid from Tucker’s penis fall onto the carpet. M.T. and E.T. testified that Tucker referred to their activities as “sex ed.” During cross-examination, which referenced previous inter

views, it was revealed that the children’s testimony contained some inconsistencies on such matters as the sequence of the games, the objects of the games, their relative stages of undress during portions of the games, who won each game, the content of the pornography, the sequence of the sex acts, and whether sex acts occurred involving M.T.’s breasts or two persons per

forming sex acts with M.T. at the same time. However, each child testified that on the day in question, M.T. performed fel

latio on Tucker and both brothers upon Tucker’s instructions and that Tucker performed cunnilingus on M.T. Contrary to Tucker’s instructions to the children not to dis

close what happened, the children informed their mother. After law enforcement was alerted, police conducted a search of the residence the children shared with their mother and Tucker. They found candy wrappers for the same type of candy the children reported Tucker had given to them. A stain found on the living room rug tested positive for semen. DNA testing showed that the semen had the same genetic profile as Tucker and that the probability of randomly selecting an unrelated- 861 - N ebraska S upreme C ourt A dva nc e S heets 301 N ebraska R eports
STATE v . TUCKER
Cite as 301 Neb. 856
individual with a DNA profile matching the sample was 1 in 752.4 quintillion. The State also introduced Y-STR DNA evi

dence found on the shorts M.T. wore on the day of the alleged offenses. This evidence is discussed in more detail in the sec

tion below. Tucker testified in his own behalf. He denied engaging in any sex acts with the children.

Y-STR DNA Evidence. The State called Bishop to testify regarding Y-STR DNA testing. Tucker’s counsel made a continuing objection to the Y-STR DNA testing and any opinions derived from such test

ing based on Daubert / Schafersman , because such evidence was “inherently unreliable and unfairly prejudicial and other

wise not relevant.” The district court overruled the continu

ing objection. Bishop testified that she is a forensic science DNA analyst at UNMC and that she had performed Y-STR DNA testing on extractions from the interior of M.T.’s shorts. Bishop stated that Y-STR DNA testing was a method of looking only at the male Y-chromosome. Bishop explained Y-STR DNA testing is often used in sexual assault cases because it can identify a male’s contribution to a sample, such as a vaginal swab, that may have many more cells from a female contributor than a male contributor. Bishop testified that UNMC has performed Y-STR DNA analysis since the early 2000’s and that UNMC has used the particular Y-STR DNA kit used in this case since 2012. Bishop stated that Y-STR DNA analysis is an accepted forensic tool in the forensic analysis community that has been available since the early 2000’s. Bishop explained that the Y-STR DNA testing process is essentially the same as autosomal DNA testing, but admitted that there is a great deal of difference between the discrimi

natory power of autosomal DNA testing versus Y-STR DNA testing. She testified that autosomal DNA testing can produce results showing that a particular profile is extremely rare in the- 862 - N ebraska S upreme C ourt A dva nc e S heets 301 N ebraska R eports
STATE v . TUCKER
Cite as 301 Neb. 856
population, but because the same Y-STR DNA profile is passed to all males in the same lineage and additionally may be pres

ent in unrelated members of the general population, Y-STR DNA testing results will not show that a particular profile is as rare. She acknowledged that a coincidental random match might occur one in several quintillion times with autosomal DNA testing but one in a few thousand times with Y-STR DNA testing. Bishop testified that Y-STR DNA testing identified Y-STR DNA present on the interior of M.T.’s shorts and that it con

sisted of a mixture of at least two male individuals. Bishop testified that she could not determine what type of cell con

tributed the Y-STR DNA profile to M.T.’s shorts or how it was deposited there. However, she stated that the major Y-STR DNA profile she found on the shorts matched Tucker at all of the loci obtained and that, consequently, Tucker was not excluded as a potential major source of the DNA tested. Bishop testified that to calculate the frequency of Tucker’s Y-STR DNA profile within the population, it was necessary to consult a database. Bishop testified and her report reflected that according to the U.S. Y-STR database, the probability of randomly selecting a second individual with the same Y-STR DNA profile, given that Tucker expresses such a profile, was 1 in 1,842 for African Americans. Tucker does not dispute the he is African American. Bishop’s report reflected that the U.S. Y-STR database was maintained by a national institute in the forensic science field. Bishop admitted that the U.S. Y-STR database had changed since her analysis because it is always gaining contributors. She further admitted that it was possible that the more indi

viduals that contribute, the better the database will be at dis

cerning the likelihood of a particular profile appearing in the general population. A forensic scientist with the Nebraska State Patrol Crime Laboratory’s biology unit also explained the statistical limita

tions arising from the patrilineal recurrence of Y-STR DNA- 863 - N ebraska S upreme C ourt A dva nc e S heets 301 N ebraska R eports
STATE v . TUCKER
Cite as 301 Neb. 856
and the possible occurrence in the general population, con

sistent with Bishop’s testimony.

Jury Verdict and Sentencing. The jury returned a verdict finding Tucker guilty on all charges. The district court ordered a presentence investigation report (PSR). The PSR reflected that Tucker, then age 33, had a traumatic childhood. Tucker’s father was not involved in his life, and he reported that he and his 10 siblings all have dif

ferent fathers. Tucker grew up in an area where gang crime and drugs were prevalent. He reported that his mother was a drug user and that he “‘had to find ways to eat and live.’” As a child, he witnessed his mother shoot her boyfriend, and he developed post-traumatic stress disorder as a result. He has also been diagnosed with paranoid schizophrenia, bipolar dis

order, and manic depression. Tucker has been involved in criminal activity since his youth. His criminal history includes a term of probation and incarceration for forgery and escape and other jail terms of considerable length for theft. His other offenses include a num

ber of drug charges, false information, false reporting, failure to appear, attempted tampering with a witness, and various traffic offenses. Tucker had completed an associate degree in theology and anthropology, and he wanted to continue his education. At the time of the present offenses, he was an owner-employee of an aquatic pet store. In the past, Tucker had worked as a dish

washer, cook, and telemarketer. When he was not employed, he supported himself by selling marijuana. The PSR noted that Tucker had refused to take responsibility for the crimes charged, consistently maintaining that he had not committed them and declining to participate in risk assessment for sex offenses. The PSR also included a victim impact letter from the children’s mother. She stated that Tucker’s crimes had led to a deterioration of her relationships with her children and behavior issues.- 864 - N ebraska S upreme C ourt A dva nc e S heets 301 N ebraska R eports
STATE v . TUCKER
Cite as 301 Neb. 856
At the sentencing hearing, the district court stated that it had considered the evidence at trial and the PSR in their entirety, particularly Tucker’s pattern of criminal behavior and failure to take responsibility for his actions or empathize with the victims in this case. The district court noted that its sentencing took into account the nature and circumstances of the crimes and Tucker’s history, character, and condition. The district court sentenced Tucker to 30 to 50 years’ imprisonment for first degree sexual assault of a child and 10 to 20 years’ imprisonment for each of the two counts of incest, with all sentences to be served consecutively. Tucker now appeals his convictions and sentences.

ASSIGNMENTS OF ERROR Tucker assigns, rephrased, (1) that the district court erred in admitting unreliable Y-STR DNA evidence, causing undue prejudice; (2) that the evidence was insufficient to prove the crimes charged; and (3) that the district court abused its discre

tion in imposing excessive sentences.

STANDARD OF REVIEW [1] An appellate court reviews for abuse of discretion a trial court’s evidentiary rulings on relevance, whether the probative value of evidence is substantially outweighed by the danger of unfair prejudice, and the sufficiency of a party’s foundation for admitting evidence. State v. Trotter , 299 Neb. 392, 908 N.W.2d 656 (2018). [2] The standard for reviewing the admissibility of expert testimony is abuse of discretion. State v. Oliveira-Coutinho

, 291 Neb. 294, 865 N.W.2d 740 (2015). [3] In reviewing a criminal conviction for a sufficiency of the evidence claim, whether the evidence is direct, circum

stantial, or a combination thereof, the standard is the same: An appellate court does not resolve conflicts in the evidence, pass on the credibility of witnesses, or reweigh the evidence; such matters are for the finder of fact. The relevant question for an appellate court is whether, after viewing the evidence in- 865 - N ebraska S upreme C ourt A dva nc e S heets 301 N ebraska R eports
STATE v . TUCKER
Cite as 301 Neb. 856
the light most favorable to the prosecution, any rational trier of fact could have found the essential elements of the crime beyond a reasonable doubt. State v. Wells , 300 Neb. 296, 912 N.W.2d 896 (2018). [4] An appellate court will not disturb a sentence imposed within the statutory limits absent an abuse of discretion by the trial court. State v. Ortega , 290 Neb. 172, 859 N.W.2d 305 (2015).

ANALYSIS Admissibility of Y-STR DNA Evidence. Tucker challenges the admission of the Y-STR DNA testing and any opinions derived from such testing. His brief contends that the probative value of this evidence was outweighed by its prejudicial effect because the evidence is unreliable. We understand Tucker to be making two basic arguments against the admissibility of the Y-STR DNA evidence. The primary argument is a contention that the inherent nature of Y-STR DNA evidence makes its admission unfairly prejudicial in any case. The second challenges the reliability of the conclusions regarding the Y-STR DNA evidence reached in this case. We take up each of these contentions in turn. [5-9] We first address Tucker’s arguments that the Y-STR DNA evidence was unfairly prejudicial. Evidence is relevant if it tends in any degree to alter the probability of a material fact. State v. Grant , 293 Neb. 163, 876 N.W.2d 639 (2016). Under Neb. Evid. R. 403, Neb. Rev. Stat. § 27-403 (Reissue 2016), relevant evidence may be excluded if its probative value is sub

stantially outweighed by the danger of unfair prejudice. Grant,
supra. Most, if not all, evidence offered by a party is calculated to be prejudicial to the opposing party. State v. Chauncey , 295 Neb. 453, 890 N.W.2d 453 (2017). Unfair prejudice means an undue tendency to suggest a decision based on an improper basis. Id . It speaks to the capacity of some concededly relevant evidence to lure the fact finder into declaring guilt on a ground different from proof specific to the offense charged, commonly on an emotional basis. Id

.- 866 - N ebraska S upreme C ourt A dva nc e S heets 301 N ebraska R eports
STATE v . TUCKER
Cite as 301 Neb. 856
Tucker’s primary argument against the admission of the Y-STR DNA evidence is that juries will inevitably base their decision on an improper basis by incorrectly perceiving the Y-STR DNA “match” testimony as conclusively connecting the defendant to the sample. Tucker asserts that jurors are inclined to think of any evidence of a DNA “match” of having an extremely small probability of being the result of coinci

dence. But, as he correctly points out, the Y-STR DNA testing in this case led to a 1-in-1,842 chance of a coincidental match. According to Tucker, this relatively greater chance of a random match renders the evidence “completely unreliable.” Brief for appellant at 37. We have previously recognized a risk that a jury might give undue weight to DNA evidence if it is introduced with

out proper context. See State v. Johnson , 290 Neb. 862, 862 N.W.2d 757 (2015). In Johnson , we observed that “‘[b]ecause the potential precision of DNA testing is so well known, a jury might assume that any DNA profile match is extremely unlikely and therefore extremely probative’—even when this is not true.” 290 Neb. at 883, 862 N.W.2d at 774, quoting Peters v. State , 18 P.3d 1224 (Alaska App. 2001). We have not, however, concluded that the appropriate measure to pre

vent a jury from making such an assumption is the wholesale exclusion of DNA evidence falling below a certain threshold of precision. Rather, we have emphasized the need for evi

dence of DNA testing to be accompanied by evidence of the statistical significance of the findings if it is to be admitted. Johnson, supra. In this case, Tucker cannot contend that the State sought to introduce the Y-STR DNA evidence without the necessary sta

tistical context. As we have noted, the State introduced much evidence regarding the statistical context for the Y-STR DNA evidence. The jury heard explanations of the relative probative value of Y-STR DNA testing and autosomal DNA testing. Both forensic scientists testified that males share the same Y-STR DNA profile with other males in the same paternal lineage,- 867 - N ebraska S upreme C ourt A dva nc e S heets 301 N ebraska R eports
STATE v . TUCKER
Cite as 301 Neb. 856
as well as others in the general population. Their testimony clearly illustrated that due to this recurrence, Y-STR DNA testing results are not as probative as autosomal DNA test

ing results. They both explained that Y-STR DNA statistical analysis would not render coincidental random match prob

abilities such as one in several hundred quintillions, showing a particular profile is extremely rare in the population. Instead, Bishop testified, Y-STR DNA testing might produce a random match probability of one in a few thousand, as it did in thiscase, where Y-STR DNA statistical analysis revealed a 1-in1,842 probability for African-American contributors that a ran

dom Y-STR DNA profile unrelated to this case would match the profile found on M.T.’s shorts. Because the Y-STR DNA testing results were accompanied by the required statistical context, its admission was consistent with the principles we set forth in Johnson

. Moreover, we do not believe that Y-STR DNA evidence is so unique that something other than the principles of Johnson should govern its admissibility. The probabilities of a coinci

dental match may be exponentially greater with Y-STR DNA evidence than with autosomal DNA evidence, but, if those differences are explained to the jury, we see no reason why jurors would be incapable of grasping the difference. We have previously rejected claims that jurors would not be capable of assigning appropriate weight to “the statistical analysis that accompanies DNA evidence,” State v. Bauldwin , 283 Neb. 678, 703, 811 N.W.2d 267, 288 (2012), and reject any suggestion that would be the case with Y-STR DNA evidence. Y-STR DNA evidence may be less probative than other DNA evidence, but if we were to find it inherently prejudicial, as Tucker urges, we would be treating such evidence differ

ently from other types of evidence that have similar probative value and that are introduced for the same purpose. As the district court and other courts have observed, Y-STR DNA evi

dence can be used in much the same manner as shoe imprint evidence. Shoe imprint evidence is routinely admitted to show- 868 - N ebraska S upreme C ourt A dva nc e S heets 301 N ebraska R eports
STATE v . TUCKER
Cite as 301 Neb. 856
that an imprint at a crime scene matches shoes owned by a defendant even though any number of individuals may own shoes identical to the defendant’s. The coincidence that [a Y-STR DNA] profile matches that of defendant is probative of his guilt in the same man

ner as if he had owned shoes that matched a foot imprint found at the crime scene. It is up to the jury to weigh the probative value of that evidence in light of the fact that a significant number of other individuals may possess the same profile. State v. Calleia , 414 N.J. Super. 125, 152, 997 A.2d 1051, 1066 (2010), reversed on other grounds 206 N.J. 274, 20 A.3d 402 (2011). See, also, People v. Stevey , 209 Cal. App. 4th 1400, 148 Cal. Rptr. 3d 1 (2012). Finally, we note that our conclusion that the Y-STR DNA evidence introduced in this case was not unfairly prejudi

cial is not a novel conclusion. Courts in a number of other states have reached the same conclusion. See, e.g., State v. Escalante-Orozco , 241 Ariz. 254, 386 P.3d 798 (2017), abro

gated on other grounds, State v. Escalante , 245 Ariz. 135, 425 P.3d 1078 (2018) (Y-STR profile evidence is not mislead

ing, nor is its probative value outweighed by risk of unfair prejudice; jury is capable of understanding limited proba

tive value of this evidence and giving it whatever weight it deserves); State v. Jones , 345 P.3d 1195 (Utah 2015) (Y-STR DNA evidence properly explained to jury such that risk of unfair prejudice through confusing or misleading jury did not substantially outweigh probative value of evidence); People v. Wood , 307 Mich. App. 485, 862 N.W.2d 7 (2014), vacated in part on other grounds 498 Mich. 914, 871 N.W.2d 154 (2015) (limitations of Y-STR DNA testing were presented to jury such that there was no danger of confusion or other unfair prejudice that would substantially outweigh proba

tive value). Having rejected Tucker’s argument that Y-STR DNA evi

dence is inherently unfairly prejudicial, we move to Tucker’s- 869 - N ebraska S upreme C ourt A dva nc e S heets 301 N ebraska R eports
STATE v . TUCKER
Cite as 301 Neb. 856
assertion that the testimony offered regarding the Y-STR DNA evidence in this case was unreliable. Here, Tucker claims that the database used by Bishop to arrive at her statistical conclu

sions may not be representative of the population in a given area and that therefore, there is a risk that Tucker’s Y-STR DNA is even more common than Bishop acknowledged and thus there is an even greater chance of a coincidental match. This seems to be an attempt at a Daubert / Schafersman chal

lenge, even though Tucker’s brief does not cite to Daubert / Schafersman or address its framework. But even if we liberally construed Tucker’s brief as having framed his argument as a Daubert / Schafersman issue, the argument fails. Tucker’s argument is premised in part on contentions about the U.S. Y-STR database made in articles published in 2003. Bishop, however, testified at the Daubert / Schafersman hearing that she was familiar with the articles Tucker relies upon. She explained that she found these articles to be irrelevant, because they were about very small sample sizes and Y-STR DNA sci

ence has improved since their publication. In fact, she testified that the U.S. Y-STR database upon which she relied was not even established at the time the articles upon which Tucker bases his challenge were written. The remaining article Tucker cites to support this argument was not presented to the district court and is not in the record before us for consideration. See State v. Patton , 287 Neb. 899, 845 N.W.2d 572 (2014) (party’s brief may not expand evidentiary record). Given Bishop’s tes

timony concerning the articles Tucker offered to the district court, we see no abuse of discretion in the admission of the Y-STR DNA evidence. In sum, we conclude that the Y-STR DNA evidence in this case did not suggest a decision based on an improper basis and that thus, its prejudicial effect did not outweigh its probative value. Moreover, Tucker’s Daubert / Schafersman arguments also fail. Therefore, the district court did not abuse its discre

tion in admitting such evidence at trial.- 870 - N ebraska S upreme C ourt A dva nc e S heets 301 N ebraska R eports
STATE v . TUCKER
Cite as 301 Neb. 856
Sufficiency of Evidence. We next address Tucker’s argument that the evidence was not sufficient to support his convictions. The relevant ques

tion when such a challenge is made is “whether, after viewing the evidence in the light most favorable to the prosecution, any rational trier of fact could have found the essential ele

ments of the crime beyond a reasonable doubt.” State v. McCurdy, ante p. 343, 351, 918 N.W.2d 292, 298 (2018). Tucker, however, does not contend that there was no evidence of the essential elements of either first degree sexual assault of a child or incest. And, given the testimony at trial that Tucker penetrated M.T.’s mouth with his penis when M.T. was 11 years old and Tucker was 31 years old; that Tucker performed cunnilingus on M.T.; that Tucker placed an electric toothbrush on M.T.’s vagina; and that upon Tucker’s instruc

tions, M.T. performed fellatio on E.T. and R.T., and E.T. and R.T. performed cunnilingus on M.T., such an argument is not available to him. Instead, Tucker argues that because the children “did not testify to a cohesive story either individually or collectively,” brief for appellant at 43, no rational juror could have found Tucker guilty beyond a reasonable doubt. In other words, Tucker is asking us to reweigh the evidence and find that the testimony of the children was not credible. “But that is not the role of an appellate court.” State v. Jones , 296 Neb. 494, 499, 894 N.W.2d 303, 307 (2017). [10] The credibility and weight of witness testimony are for the jury to determine, and witness credibility is not to be reassessed on appellate review. State v. Archie , 273 Neb. 612, 733 N.W.2d 513 (2007). Our task is limited to determining whether, after viewing the evidence in the light most favorable to the prosecution, any rational trier of fact could have found beyond a reasonable doubt that Tucker committed the charged offenses. See id. Based on the evidence summarized above, we conclude it could.- 871 - N ebraska S upreme C ourt A dva nc e S heets 301 N ebraska R eports
STATE v . TUCKER
Cite as 301 Neb. 856

Excessive Sentences. Finally, we address Tucker’s claim that he received exces

sive sentences. Tucker does not dispute that the sentences imposed were within statutory limits. Rather, he argues only that the district court did not meaningfully consider his child

hood trauma, mental condition, and need for rehabilitation. We conclude that the district court did not abuse its discretion in sentencing Tucker. [11-14] Where a sentence imposed within the statutory limits is alleged on appeal to be excessive, the appellate court must determine whether a sentencing court abused its discre

tion in considering and applying the relevant factors as well as any applicable legal principles in determining the sentence to be imposed. State v. Russell , 299 Neb. 483, 908 N.W.2d 669 (2018). Relevant factors customarily considered and applied are the defendant’s (1) age, (2) mentality, (3) education and experience, (4) social and cultural background, (5) past crimi

nal record or record of law-abiding conduct, and (6) motiva

tion for the offense, as well as (7) the nature of the offense and (8) the amount of violence involved in the commission of the crime. Id. The appropriateness of a sentence is necessar

ily a subjective judgment and includes the sentencing judge’s observation of the defendant’s demeanor and attitude and all the facts and circumstances surrounding the defendant’s life. State v. Steele , 300 Neb. 617, 915 N.W.2d 560 (2018). And generally, it is within a trial court’s discretion to direct that sentences imposed for separate crimes be served either concur

rently or consecutively. State v. Leahy, ante p. 228, 917 N.W.2d 895 (2018). Our review of the record demonstrates that the district court properly considered and applied the necessary sentencing fac

tors. The PSR shows that Tucker exhibited mental illness after having grown up in an environment of poverty, crime, drug use, instability, and trauma. Certainly, these disadvantages were relevant to the sentencing calculus, but the district court stated that it considered the PSR in its entirety, and we have- 872 - N ebraska S upreme C ourt A dva nc e S heets 301 N ebraska R eports
STATE v . TUCKER
Cite as 301 Neb. 856
no reason to believe the district court did not weigh those dis

advantages against other factors. Those other factors, however, would include Tucker’s significant pattern of criminal behav

ior and the nature of the offenses at issue. On this point, the record shows that Tucker’s crimes against the children in this case were particularly serious. Tucker used games and candy to systematically lure children in his care into participating in acts that will have a lasting negative impact on their lives. And as the district court emphasized, Tucker has not taken responsibil

ity for his actions. Having reviewed the record and the district court’s remarks in light of the familiar sentencing factors set forth above, we conclude that the district court did not abuse its discretion in sentencing Tucker within statutory limits.

CONCLUSION We conclude that the district court did not abuse its discre

tion in admitting Y-STR DNA evidence at trial. We further determine that the evidence presented at trial was sufficient to support Tucker’s convictions and that the district court did not abuse its discretion in sentencing him. Consequently, we affirm. A ff i rmed

. M i ller

- L erma n , J., not participating.