Illinois Official Reports

Appellate Court

People v. Zapata, 2014 IL App (2d) 120825

Appellate Court 

Caption

THE PEOPLE OF THE STATE OF ILLINOIS, Plaintiff-Appellee, v. 

RODOLFO ZAPATA, Defendant-Appellant.

District & No. Second District

Docket No. 2-12-0825

Filed April 15, 2014

Held

(Note: This syllabus 

constitutes no part of the 

opinion of the court but 

has been prepared by the 

Reporter of Decisions 

for the convenience of 

the reader.)

Defendant’s conviction for criminal sexual assault was upheld on 

appeal over his contention that under the plain-error rule, the trial 

court erred in admitting testimony about Y-STR analysis of DNA 

found on complainant’s underwear without a Frye hearing to 

determine whether the methodology or scientific principle involved 

was sufficiently established to have gained general acceptance, since a 

Frye hearing was unnecessary in view of the unequivocal and 

undisputed prior judicial decisions and technical writings on the 

subject.

Decision Under 

Review

Appeal from the Circuit Court of Kendall County, No. 11-CF-28; the 

Hon. John A. Barsanti, Judge, presiding.

Judgment Affirmed.

Counsel on

Appeal

Thomas A. Lilien and Barbara R. Paschen, both of State Appellate 

Defender’s Office, of Elgin, for appellant.

Eric C. Weis, State’s Attorney, of Yorkville (Lawrence M. Bauer and 

Marshall M. Stevens, both of State’s Attorneys Appellate Prosecutor’s 

Office, of counsel), for the People.
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Panel PRESIDING JUSTICE BURKE delivered the judgment of the court, 

with opinion.

Justices McLaren and Hudson concurred in the judgment and opinion.

OPINION

¶ 1 Following a jury trial in the circuit court of Kendall County, defendant, Rodolfo Zapata, 

was found guilty of criminal sexual assault (720 ILCS 5/12-13(a)(2) (West 2010)) and was 

sentenced to an eight-year prison term. On appeal, defendant argues that it was error to admit 

testimony about Y-STR analysis of a specimen of DNA found on the complaining witness’s 

underwear. We affirm.

¶ 2 At trial, the State presented evidence that on June 27, 2010, the complaining witness, 

Corinne M., and her friend, Pedro Garcia, were drinking at a bar in Yorkville with a group of 

people that included, among others, defendant, Lino Garcia, and Chris Garcia. Lino and Chris 

Garcia were brothers and defendant was their cousin on their mother’s side. Pedro was not 

related to Lino and Chris. Corinne testified that she drank beer and shots of Red Bull and some 

type of liquor. After the bar closed, the group went to a house in Yorkville where Lino, Chris, 

and defendant resided. The group continued to drink, played cards, and socialized. Corinne and 

Pedro planned to sleep over at the house that night, and Corinne borrowed a pair of shorts to 

sleep in. After changing into the shorts, Corinne joined Pedro, Lino, and defendant in the 

family room. At some point, Lino and defendant left to go to bed. Corinne and Pedro stayed up 

talking and playing cards. They also continued drinking. Corinne testified that she started to 

feel dizzy after having some wine. She went into the bathroom and threw up into the toilet. She 

then lay down on the bathroom floor and fell asleep.

¶ 3 Corinne testified that, when she awoke, she felt someone’s penis in her vagina. She 

observed that defendant was “spooning” her. Her shorts and underwear had been pulled down.

She started yelling at defendant and he ran out of the bathroom. Lino and Pedro woke up and 

Lino helped Corinne look for defendant in the house. Corinne testified that she did not find 

defendant. Corinne took a shower, and Pedro then drove her to the emergency room at an 

Aurora hospital. When Corinne got dressed after her shower, she did not put on the pair of 

underwear she had been wearing when the sexual assault occurred. She took that pair of 

underwear to the hospital and it was preserved for forensic analysis.

¶ 4 At the hospital, a rape kit was performed. William Enselme, a forensic scientist employed 

by the Illinois State Police, testified that he tested vaginal, oral, and rectal swabs collected in 

the rape kit for the presence of semen and saliva. The tests were negative for both substances.

Enselme visually examined head and pubic hair combings, but found nothing that would 

warrant further analysis. He noted “spec[k]s of debris” on scrapings from underneath 

Corinne’s fingernails. Enselme also examined Corinne’s underwear. He noted that the crotch 

area was stained with a slightly yellowish substance. The stain measured 51⁄2 inches long by 1 

inch wide. Tests performed on the substance indicated (but did not confirm) the presence of 

semen. Enselme did not detect sperm in the substance.
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¶ 5 Two other forensic scientists employed by the Illinois State Police–Lyle Boicken and 

Katherine Sullivan–testified about DNA testing performed on the substance found on 

Corinne’s underwear. Boicken testified that the specimen of the substance was not suitable 

polymerase chain reaction short tandem repeat (PCR-STR) analysis. PCR-STR analysis 

generates a DNA profile based on short tandem repeats. Boicken testified that short tandem 

repeats are “short segments of DNA which are repeated in different individuals.” Boicken 

explained that the sequence “ACTG”1 might repeat 10 times at a particular location in one 

individual’s DNA and 15 times at the same location in the DNA of another individual. By 

determining the number of repeats at a number of different loci, a profile can be compiled.

Boicken testified that 14 to 16 loci are used, if possible. However, in order to be suitable for 

PCR-STR analysis, a specimen must contain either a certain amount of DNA or a certain 

ratio of male DNA to female DNA. When a specimen does not meet the applicable criteria 

for PCR-STR analysis, a different type of analysis–Y-STR–might be possible. According to 

Boicken, the specimen in this case was suitable for Y-STR analysis.

¶ 6 Sullivan testified that she performed a Y-STR analysis on the specimen from Corinne’s 

underwear. She described the Y-STR analysis as “short tandem repeat or STR testing that’s 

done exclusively on sites on just the Y chromosome.” Asked how the “Y chromosome or 

Y-STR differ[s] from male to male,” Sullivan responded that “it would be expected to differ 

from male to male except in cases where the individuals are paternally related.” Sullivan 

explained that “[b]ecause the Y chromosome is passed in its entirety from father to son, I 

would expect that any male would have the same Y-STR profile as his father, any of his 

brothers from the same father, and so on through the family tree.” She further explained that

the profile developed by determining the number of repeats at each tested Y chromosome 

locus describes a haplotype. Sullivan’s testimony indicated that detection of more than one 

haplotype in a given specimen could occur when the specimen contains the DNA of more 

than one male or where, due to a genetic anomaly, the DNA of a female contributor to the 

specimen contains Y chromosomes.

¶ 7 According to Sullivan, Y-STR testing on the DNA specimen from Corinne’s underwear 

indicated the presence of a single haplotype. Sullivan also performed Y-STR testing on a 

sample of Corinne’s blood. As Sullivan expected, the testing indicated “no Y-STR haplotype 

results at all.” Sullivan also performed Y-STR testing on DNA from a buccal swab 

performed on defendant. The test indicated a single haplotype, which matched the haplotype 

identified in the test performed on the specimen from Corinne’s underwear. Sullivan’s direct 

testimony concluded with the following exchange:

“Q. Was the defendant therefore included or excluded from contributing his DNA 

to the stain in [Corinne’s underwear]?

A. He would be included.

Q. He was not excluded?

A. That’s correct.”

¶ 8 Defendant’s sole argument on appeal is that, before permitting the State to offer 

testimony about the results of the Y-STR test conducted on a DNA specimen from the 

 1

These letters refer to the different nucleotides–adenine, cytosine, thymine, and guanine–that link 

together sequentially to form a strand of DNA. See People v. Williams, 238 Ill. 2d 125, 130 n.1 (2010), 

aff’d sub nom. Williams v. Illinois, 567 U.S. ___, 132 S. Ct. 2221 (2012).
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victim’s panties, the trial court was obligated to conduct a hearing to determine whether the 

testimony satisfied the test set forth in Frye v. United States, 293 F. 1013 (D.C. Cir. 1923), 

which governs the admissibility of new or novel scientific evidence in Illinois. See Ill. R. 

Evid. 702 (eff. Jan. 1, 2011). Pursuant to Frye, a witness may offer an opinion based on such 

evidence “only if the methodology or scientific principle upon which the opinion is based is 

‘sufficiently established to have gained general acceptance in the particular field in which it 

belongs.’ ” In re Commitment of Simons, 213 Ill. 2d 523, 529-30 (2004) (quoting Frye, 293 F. 

at 1014).

¶ 9 Defendant acknowledges that, because he did not object at trial to the admissibility of the 

testimony or raise the issue in his posttrial motion, he has forfeited review of the issue that he 

now raises on appeal. See People v. Enoch, 122 Ill. 2d 176, 186 (1988) (objection both at trial 

and in a posttrial motion required to preserve an issue for appeal). Defendant contends, 

however, that the issue is reviewable under the plain-error rule. The plain-error rule permits 

appellate review, notwithstanding forfeiture, where “(1) a clear or obvious error occurred and 

the evidence is so closely balanced that the error alone threatened to tip the scales of justice 

against the defendant; or (2) a clear or obvious error occurred, and the error is so serious that 

it affected the fairness of the defendant’s trial and the integrity of the judicial process, 

regardless of the closeness of the evidence.” In re Jonathon C.B., 2011 IL 107750, ¶ 70. “[I]n 

addressing a plain-error argument, this court first considers whether error occurred at all.” Id.

As explained below, we conclude that a Frye hearing to determine whether Y-STR testing 

has gained general acceptance was not necessary. Accordingly no error occurred.

¶ 10 Our supreme court has held that “[a] court may determine the general acceptance of a 

scientific principle or methodology in either of two ways: (1) based on the results of a Frye

hearing; or (2) by taking judicial notice of unequivocal and undisputed prior judicial 

decisions or technical writings on the subject.” (Emphasis added.) People v. McKown, 226 

Ill. 2d 245, 254 (2007). The question of whether evidence is admissible under Frye is subject 

to de novo review. Furthermore, “[i]n conducting such de novo review, the reviewing court 

may consider not only the trial court record but also, where appropriate, sources outside the 

record, including legal and scientific articles, as well as court opinions from other 

jurisdictions.” Simons, 213 Ill. 2d at 531.

¶ 11 Before proceeding, a brief overview of DNA profiling techniques is in order. In People v. 

Barker, 403 Ill. App. 3d 515, 527-28 (2010), the court observed as follows:

“In its earliest form, DNA forensic technology focused on those parts of the DNA 

molecule where there is a significant variation of base pair patterns. [Citation.] Over 

the years, the technology evolved and now focuses on a class of polymorphisms in 

DNA called ‘short tandem repeats’ (STRs), which are shorter in base pair length.

STRs are readily amplified by a process known as ‘polymerase chain reacion’ [sic] 

(PCR) technology. The number of repeats in STR markers can be highly variable 

among individuals, which make them particularly desirable for identification 

determinations. [Citation.] The current technology of STRs focuses on the small 

noncoding regions of the DNA molecule. The number of repeats of a specific STR 

sequence present at a given locus, combined over a designated number of loci, creates 

a unique DNA ‘profile’ of an individual. [Citation.]

***
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Y-STR testing examines the Y chromosome that passed from father to son.

Y-STRs are short repeats found solely in the male-specific Y chromosome that code 

for male sex determination, spermatogenesis, and other male-related functions. ‘The 

technique was developed in part to identify a male contributor or contributors in cases 

of sexual assault, where DNA from both the female and male[ ] is present in a vaginal 

swab.’ [Citation.]”

¶ 12 In Barker, the defendant, who had been convicted of first-degree murder and aggravated 

criminal sexual assault, later petitioned the trial court to order DNA testing. The defendant 

asked for three types of tests to be performed: short tandem repeat (STR), polymerase chain 

reaction (PCR), and restriction fragment length polymorphism (RFLP). Id. at 521-22. On 

appeal from the denial of the request, the defendant additionally asked for Y-STR and 

mitochondrial DNA testing. Id. at 524. In the course of its analysis, the Barker court quoted

one commentator’s observation that Y-STR testing has “ ‘received mixed responses 

judicially in terms of its admissibility at trial’ ” (id. at 528 (quoting Jules Epstein, “Genetic 

Surveillance”–The Bogeyman Response to Familial DNA Investigations, 2009 U. Ill. J.L. 

Tech. & Pol’y 141, 148)). However, the only negative judicial response cited by that 

commentator was an unpublished decision of Minnesota’s court of appeals holding that the 

trial testimony of the forensic scientist who conducted Y-STR testing was insufficient to 

establish general acceptance of the methodology. Epstein, supra at 148 n.58 (citing Yeboah v. 

State, No. A07-0739, 2008 WL 2020449, at *1 (Minn. Ct. App. Aug. 5, 2009)). The 

Minnesota court did not draw any ultimate conclusion about whether Y-STR analysis is 

generally accepted.

¶ 13 In the present case, although defendant notes the Barker court’s somewhat oblique 

suggestion that Y-STR testing is controversial, he completely ignores the Barker court’s 

more salient observation that “defendant’s trial took place in March of 2005, at which point 

all three of the DNA procedures requested in defendant’s original motion, plus the two tests 

he now requests on appeal, had been judicially recognized as generally accepted by the 

relevant scientific community.” (Emphasis added.) Barker, 403 Ill. App. 3d at 525. As noted, 

the Y-STR test was one of the two additional tests that the defendant in Barker requested on 

appeal.

¶ 14 A recent decision from the California Court of Appeal, People v. Stevey, 148 Cal. Rptr. 

3d 1, 9-11 (Cal. Ct. App. 2012), confirms that Y-STR testing has gained general acceptance:

“Although Y-STR testing *** [has] been generally accepted by the scientific 

community as reported by courts across the country, defendant contends the trial 

court erred by refusing to hold an evidentiary hearing to establish that Y-STR testing 

is generally accepted. (See, e.g., State v. Calleia (2010) 414 N.J. Super. 125, 148-149, 

997 A.2d 1051 (Calleia), reversed on other grounds in State v. Calleia (2011) 206 

N.J. 274, 20 A.3d 402; Curtis v. State (2006) 205 S.W.3d 656, 660-661 (Curtis); State 

v. Murray (2008) 285 Kan. 503, 512-514, 174 P.3d 407; State v. Lee (2007) 964 So.

2d 967, 983; Wagner v. State (2005) 160 Md. App. 531, 547-548, 864 A.2d 1037 

(Wagner); People v. Klinger (2000) 185 Misc. 2d 574, 580-581, 713 N.Y.S.2d 823 

(Klinger).) He is mistaken. Y-STR testing does not embrace new scientific 

techniques. [Citation.]
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‘[T]he use of polymerase chain reaction and short tandem repeats technology to 

analyze a mixed-source forensic sample is neither a new or novel technique or 

methodology.’ [Citations.] ***

Recent cases in New Jersey and Washington are particularly helpful in 

understanding the basic science, the similarity between PCR/STR and Y-STR testing, 

and the scientific response to Y-STR testing. In Calleia, supra, 997 A.2d 1051, the 

court explained: ‘The analytical procedure followed in Y-STR DNA testing is 

identical to that followed in autosomal STR DNA testing. The sample is extracted in 

the same manner, amplified by the PCR method, tagged with a primer, and detected 

in the genetic analyzer. The data is collected and represented in exactly the same way.

The only procedural distinction is that the primer included in the test kit for Y-STR 

DNA analysis contains markers for the Y-STR loci specified by SWGDAM [a 

scientific advisory board]; the primer included in the test kit for autosomal STR DNA 

analysis contains markers for loci on all twenty-three chromosome pairs. The major 

difference between autosomal STR DNA analysis and Y-STR DNA analysis is in the 

interpretation and application of the test results.’ [Citation.]

The similarity between PCR/STR testing and Y-STR testing was also observed in 

State v. Bander (2009) 150 Wash. App. 690, 208 P.3d 1242 (Bander). ‘ReliaGene 

used a PCR-based process known as YSTR testing to type the DNA samples it tested. 

YSTR amplification is essentially the same as the PCR-STR process that [the state 

crime lab DNA analyst] used, except that it permits the analysis of only male DNA in 

a mixed-source sample that also contains DNA from a female contributor.’ [Citation.]

* * *

Most importantly for our purposes, it was ‘established that Y-STR DNA analysis 

is a “non-experimental, demonstrable technique” that is widely accepted by forensic 

scientists.’ [Citation.] The [Calleia] court concluded that ‘there is a general 

acceptance of Y-STR DNA analysis in the scientific community.’ [Citation.]

Similarly, in Curtis [citation], the appellate court affirmed the trial court’s finding that 

‘the YSTR methodology had been validated “internally and externally” and subjected 

to peer review, that it was generally accepted in the scientific community, and that the 

YSTR evidence was reliable and relevant.’ [Citation.]”

¶ 15 Defendant cautions us against reliance on the principal cases that the Stevey court cited in 

the above excerpt: Bander and Calleia. Defendant questions the significance of the Bander

court’s observation that Y-STR analysis is “essentially the same” as the PCR-STR process, 

except that Y-STR analysis permits isolation of male DNA in a mixed source sample.

Bander, 208 P.3d at 1246. According to defendant, that observation “[raises] many questions, 

the most basic of which is ‘How (and why) does Y-STR permit a different analysis from 

PCR-STR.’ ” The argument is meritless. The Bander court explained that “[t]he DNA 

segments that are the focus of YSTR testing are inherited as a block through an individual’s 

paternal lineage.” Id. According to Bander:

“This block is known as a haplotype–‘a set of closely linked genetic markers present 

on one chromosome which tend to be inherited together.’ National Forensic Science 

Technology Center, President’s DNA Initiative: DNA Analyst Training Glossary, 

http:// www.nfstc.org/pdi/glossary.htm#H (last visited May 12, 2009). All men in the 
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same paternal lineage have the same DNA profile at these markers on their Y 

chromosomes.” Id.

In other words, Y-STR testing enables a DNA analyst to determine whether a known male 

whose DNA has been profiled can be excluded as the source of Y chromosomes in a 

specimen consisting of a mixture of DNA from a female source and an unknown male 

source.

¶ 16 With respect to Calleia, defendant argues that, because a Frye hearing was held in that 

case, the Calleia court’s determination that Y-STR testing satisfies the general acceptance 

test is not authority that we may dispense with a Frye hearing in this case. As discussed, 

however, under Illinois law, general acceptance of a given type of scientific evidence need 

not be litigated separately in each case in which the evidence is offered. Moreover, given the 

considerable additional support (as described above) for the proposition that Y-STR testing 

has gained general acceptance in the relevant field, we need not decide whether Calleia, by 

itself, would be sufficient authority for admission of Y-STR test evidence in an Illinois court.

¶ 17 For the foregoing reasons, the judgment of the circuit court of Kendall County is 

affirmed.

¶ 18 Affirmed.