COURT OF APPEALS OF VIRGINIA 

Present: Chief Judge Moon, Judges Coleman and Willis 

Argued at Salem, Virginia 

DAVID ALAN KEEN 

 OPINION BY 

v. Record No. 0226-96-3 CHIEF JUDGE NORMAN K. MOON 

COMMONWEALTH OF VIRGINIA 

FROM THE CIRCUIT COURT OF TAZEWELL COUNTY 

Donald R. Mullins, Judge 

 Jerry C. Lyell (H. Shannon Cooke, on brief), 

for appellant. 

 John C. McLees, Jr., Assistant Attorney 

General (James S. Gilmore, III, Attorney 

General, on brief), for appellee. 

 David Alan Keen appeals his convictions of rape, sodomy, and 

statutory burglary. Keen asserts that the trial court erred in: 

(1) denying his motion for production of proficiency test data 

and results from the Virginia DNA laboratory ("state 

laboratory"); (2) allowing the Commonwealth's DNA expert to 

consider the results of DQ-alpha DNA analysis of the rapist's 

sperm in calculating the frequency with which a person of the 

rapist's genetic profile would be found in the caucasian 

population ("random-match" calculation); and (3) denying his 

request that cautionary DNA instructions be given to the jury. 

 We hold that: (1) the trial court erred in denying Keen's 

request that he be provided with proficiency testing data of the 

state laboratory where the Commonwealth's analysis was conducted 

and where the Commonwealth's DNA expert was employed, but that 
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the error was harmless; (2) the random match frequency offered by 

the Commonwealth's expert properly included the DQ-alpha analysis 

testified to by the Commonwealth's expert; and (3) that because 

the proffered jury instructions were statements of scientific 

knowledge and did not pertain to the law of the case, the trial 

court did not err in refusing the instructions. Accordingly, we 

affirm. 

 At approximately midnight on December 13, 1994, sixty-four 

year old Nancy Greer, who lived alone in her trailer, awoke and 

found a naked man kneeling over her. The man hit her repeatedly 

in the face, raped her, and anally sodomized her, causing 

injuries to her vagina and rectum. Greer struggled with her 

assailant and scratched his neck. Because she was not wearing 

her glasses, Greer was unable to see the man very well, but she 

could tell that he was tall and that he was freshly shaven. After 

assaulting Greer, the assailant fled. 

 A neighbor, awakened by Greer's screams, testified that she 

looked out her window and saw a man riding a bicycle toward 

Keen's home, which was located approximately one-half mile from 

Greer's trailer. Greer ran to a neighbor's home and told them 

that she had been raped. The neighbor telephoned the police and, 

based on Greer’s description of the assailant, directed the 

police to Keen’s residence. 

 Keen was questioned at his home and denied knowledge of the 

incident. The investigating officer noticed scratch marks on 
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Keen's neck and inquired about them. Keen responded that he did 

not know how he had received the scratches. One of Keen's 

neighbors, who had seen him the morning of the incident, 

testified that she had not seen any scratches on his neck at that 

time. 

 A police bloodhound was brought to the scene shortly after 

the attack, and it followed a scent from the crime scene to 

Keen's residence. A forensics team also investigated the crime 

scene and determined that the intruder had broken a window pane 

in order to enter Greer's trailer. A latent palm print was 

discovered on one of the broken panes of glass found inside 

Greer's trailer. A state fingerprint examiner testified that the 

palm print matched Keen's right palm print. 

 Greer later identified Keen's photograph when it was shown 

to her in a photographic line-up at the Sheriff's Department. 

Keen was arrested and taken to the station where he admitted 

having broken into Greer's trailer, but stated that he had not 

seen Greer inside and that he had only intended to steal money 

and pills. 

 Keen was charged with rape, sodomy, and statutory burglary. 

 During Keen's jury trial the Commonwealth presented DNA evidence 

based on an analysis of a vaginal cervical swab taken from Greer. 

 Evidence from RFLP and PCR analysis, two methods for testing 

DNA, was presented during trial. 

Discovery Request
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 Pursuant to Rule 3A:11, Keen requested "records of 

proficiency testing of personnel in the laboratories where RFLP 

and PCR analyses were performed in these cases" and "records of 

laboratory error rates resulting from external blind forensic DNA 

analyses or any other studies pertaining to error rates." The 

state laboratory and the Commonwealth provided Keen a memorandum 

detailing the three proficiency tests the Commonwealth's DNA 

expert, Jean Hamilton, a forensic scientist at the state 

laboratory, had performed. The memorandum provided details on 

proficiency tests 93Q, 940Q, and 9415, and indicated that 

Hamilton had passed all three tests. 

 Keen was not satisfied with the memorandum and produced two 

reports published by the Collaborative Testing Services, Inc. 

("CTS"), detailing results from laboratories nationwide. One 

report addressed proficiency test 93Q and the other addressed 

1992 results of test 92-15. The results of the 93Q test were 

published using anonymous identification numbers for each person 

taking the test at each lab so that it was not possible for 

either Keen or Hamilton to identify which results were hers. 

However, the state laboratory program manager indicated in the 

memorandum detailing Hamilton's performance on the three 

proficiency tests that Hamilton had successfully passed the test. 

 Although the state laboratory had participated in the 92-15 

 test, Hamilton had not. The laboratory results were published 

using anonymous identification numbers for each laboratory. The 
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results indicated that two of the participating laboratories had 

produced inaccurate results. Keen requested that he be provided 

with the Virginia state laboratory identification number so he 

could determine if the Virginia laboratory had been one of the 

two laboratories to make erroneous findings. The trial court, 

finding that Keen was entitled only to test results concerning 

Hamilton and that such information had been provided, denied 

Keen's objection that the Commonwealth's failure to provide the 

requested information rendered Keen's counsel unable to 

effectively cross-examine Hamilton. 

 Keen asserts that the trial court's denial of his discovery 

 request was error. Specifically, Keen asserts that he was 

entitled to the state laboratory's and Hamilton's anonymous 

identification numbers so he could make use of CTS's nationwide 

test results in presenting his defense. Rule 3A:11(b)(2) 

provides that "[u]pon written motion of an accused a court shall 

permit the accused to inspect designated books, paper, [and] 

documents . . . upon a showing that the items sought may be 

material to the preparation of his defense . . . ." We read the 

trial court's ruling denying Keen's request as a finding that 

Keen failed to meet his burden of proving that the requested 

information was "material." 

 Here, the record reflects that evidence, gathered from the 

crime scene, was examined by an employee at one of the 

laboratories reported on by CTS. The record also establishes 
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that although Hamilton individually performed the analysis of the 

evidence, her training and her work facilities were provided by 

the state laboratory. The evidence supports Keen's assertion 

that the state laboratory's proficiency ratings were probative of 

Hamilton's skills as an expert and of the laboratory's results 

generally. Thus, for purposes of this opinion we will assume 

that the trial court abused its discretion in denying Keen's 

discovery request. 

 However, assuming that the trial court erred in failing to 

find the requested proficiency test results to be material, we 

nevertheless hold that such error was harmless. 

"[N]on-constitutional error is harmless `[w]hen it plainly 

appears from the record and the evidence given at the trial that 

the parties have had a fair trial on the merits and substantial 

justice has been reached.'" Shurbaji v. Commonwealth, 18 Va. 

App. 415, 419, 444 S.E.2d 549, 551 (1994) (citations omitted). A 

criminal conviction need not be reversed if "`it plainly appears 

from the record and the evidence . . . that' the error did not 

affect the verdict. An error does not affect a verdict if a 

reviewing court can conclude without usurping the jury's fact 

finding function, that, had the error not occurred, the verdict 

would have been same." Id. at 419-20, 444 S.E.2d at 551-52. 

 Here, the record contains overwhelming evidence of Keen's 

guilt. A bicyclist was seen by a neighbor, who was awakened by 

Greer's screams, riding in the direction of Keen's home, one-half 
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mile from Greer's trailer. Keen's palm print was found on a 

broken piece of glass inside Greer's trailer. A blood hound 

traced Keen's scent from the trailer to his residence. Greer 

testified to having scratched her assailant and Keen had scratch 

marks on his neck that were not present earlier in the day. 

Finally, Keen lied to the police and ultimately admitted breaking 

into Greer's home with the alleged purpose of only stealing money 

and pills. Considering the magnitude of the evidence against 

Keen, even assuming arguendo that no DNA evidence had been 

introduced at trial, it plainly appears that the verdict would 

have been the same. Further, even if the information sought had 

been admitted and could have been used by Keen to establish that 

the state laboratory had previously made erroneous findings, this 

information would not have affected the admissibility of the DNA 

evidence, but rather, would have only affected the weight the 

fact finder accorded the DNA evidence. Accordingly, we hold that 

even assuming that trial court's denial of Keen's request was 

error, such error was harmless.1

 1 We also note that the record does not support Keen's 

counsel's complaints that the trial court's refusal to permit 

discovery of the identification numbers seriously impaired 

presentation of Keen's defense. Keen complained that he was 

unable to effectively cross-examine Hamilton because he did not 

have her identification number for the 93Q test. However, the 

record establishes that the state laboratory program manager 

provided Keen, via the Commonwealth, a complete history of 

Hamilton's proficiency testing, including information indicating 

that she had passed the 93Q test. 

 Similarly, Keen's assertion that there was some discrepancy 

in the 93Q test results, which Hamilton could not explain, 

appears to reflect a failure by Keen to recognize that eleven 

laboratories participating in the report performed only DQ-alpha 
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Random-Match Calculation

 During trial, Hamilton testified about her analysis of 

evidence gathered from the crime scene. Hamilton had been 

provided with a vaginal cervical sample from Greer that contained 

both cervical material and seminal fluid. Hamilton separated the 

material into a "sperm sample," containing the sperm material, 

and a "non-sperm sample," containing all other material. She was 

also supplied with blood samples from Greer and Keen. Hamilton 

testified that she performed two tests on all four samples, using 

what is known as PCR (polymerase chain reaction) testing.2

 

 

analysis. Consequently, while the results of those eleven 

laboratories differed from the other participants results, who 

performed additional testing, the results were nevertheless 

accurate. 

 2 PCR analysis 

 is employed to amplify small quantities of 

deoxyribonucleic acid (DNA), the molecule that carries 

genetic information unique to each individual. The 

process proceeds in three steps. In the first step, 

DNA is extracted from samples of blood, sperm, hair, or 

other body tissue, by the use of solvents, filtration, 

chemical cleaning, and separation of unwanted fractions 

in a centrifuge. This first stage is essentially the 

same as that used for the isolation of DNA in the DNA 

printing process. 

 In the second stage, the small quantity of 

isolated DNA is added to a buffer solution containing 

chemical primers and an enzyme called "TAQ polymerase." 

That solution is then placed in a heating device, 

controlled by a microprocessor, which cycles the 

solution through several successive temperature 

plateaus. After 30 or 40 of these cycles, the DNA will 

have been denatured, the primers will have annealed to 

the DNA, identifying a "gene of interest," and that 

gene will have been replicated or amplified by the 

enzyme billions of times. 

 The third stage is the typing of the amplified 

gene. Nine "allele-specific probes" are attached to a 
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Hamilton explained that she first conducted PCR DQ-alpha testing, 

involving a process whereby a piece of DNA is extracted from a 

sample and a particular area of the chromosome, identified as the 

DQ-alpha locus, is examined. At the DQ-alpha locus, humans 

display any two of six different types of alleles (gene types or 

"traits") identified as 1.1, 1.2, 1.3, 2, 3, and 4. One allele 

at the DQ-alpha locus is inherited from each parent so that every 

individual will have either two alleles of the same type or two 

different alleles. The pairings of alleles are known as the 

"genotype." Based on her analysis of Greer's and Keen's blood 

samples, Hamilton determined that they both had the same DQ-alpha 

genotype, that is, both had two type 3 alleles at the DQ-alpha 

locus. 

 Hamilton's DQ-alpha analysis of the sperm sample also 

revealed a DQ-alpha genotype of 3,3. Based on this analysis, 

nylon membrane, and the amplified DNA is flooded over 

it. The probes are designed to recognize each of the 

variants of the "gene of interest" . . . . The probes 

"light up" in the presence of the variants for which 

they are specific. [For example, the DQ-alpha] . . . 

genetic marker system has six "traits," designated, 

respectively, as 1.1, 1.2, 1.3, 2, 3 and 4. These 

traits are combined in pairs in each individual, 

because one trait is received from each parent. There 

are . . . 21 possible combinations of these traits. 

These pairings are called "genotypes." The purpose of 

the typing is to identify the genotype present in the 

amplified DNA. 

Spencer v. Commonwealth, 240 Va. 78, 96, 393 S.E.2d 609, 620 

(1990). 
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Hamilton concluded that Keen could not be eliminated as 

contributing the sperm sample found in Greer because the DQ-alpha 

of the sperm and Keen's DNA were the same. 

 Hamilton then performed a second PCR test known as 

polymarker analysis, which examines five additional areas of the 

DNA, respectively identified as LDLR, GYPA, HBGG, D7S8, and GC. 

As with the DQ-alpha locus, Hamilton explained that the alleles 

at these five locations can differ from one person to another.3

 

 Hamilton determined the following profiles for the four samples: 

Greer 

Blood Sample

Keen 

Blood Sample 

Vaginal Swab: 

Sperm Sample 

Vaginal Swab: 

Non-sperm 

Sample

LDLR BB AB AB BB 

GYPA BB AA AA BB 

HBGG AA BB BB AA 

D7S8 AA BB BB AA 

GC AC CC CC AC 

Based on this analysis, Hamilton concluded that because the 

profile of the DNA extracted from the sperm sample was the same 

as Keen's profile, Keen could not be eliminated as the 

contributor of the sperm. 

 Hamilton then calculated the frequency, or random-match 

probability, of an individual in the caucasian population 

 

 3 At LDLR, GYPA, and D7S8 there are three different possible 

combinations any person could have. At HBGG and GC, there are 

six possible combinations. 
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displaying Keen's profile as determined by the DQ-alpha and 

polymarker analysis. By multiplying together the individual 

frequencies of the five areas analyzed with the polymarker test, 

and then multiplying this result by the frequency in the 

caucasian population of people displaying a 3,3 genotype at the 

DQ-alpha locus, Hamilton determined that such a combination of 

genetic factors, or "genetic profile," would be found in only one 

of 15,000 people in the caucasian population.4

 Keen objected to Hamilton's use of the DQ-alpha analysis in 

calculating the frequency of Keen's genetic profile in the 

caucasian population. Keen asserted that because he and Greer 

had the same genotype (3,3) at the DQ-alpha locus, Hamilton could 

not say with any scientific certainty whether the 3,3 alleles she 

detected in the "crime scene materials" were contributed by Greer 

or by Keen. The trial court overruled the objection and 

 4 Because she had been unable to exclude Keen through either 

the DQ-alpha or polymarker tests, Hamilton conducted further 

analysis using the RFLP testing procedure. 

 Restriction Fragment Length Polymorphism 

(RFLP) is the most established and widely 

used DNA test to date. It has been endorsed 

by the Office of Technology Assessment of the 

United States Congress as well as the 

National Research Council. Like PCR testing, 

RFLP produces genetic band patterns that 

technicians compare to the sample given by 

the test subject. 

Paul B. Tyler, The Kelly-Frye "general acceptance" standard 

remains the rule for admissibility of novel scientific evidence: 

People v. Leahy, 22 PEPP. L. REV. 1274, 1291-92 (1995) (citations 

omitted). However, Hamilton testified that she was unable to 

obtain conclusive results from the RFLP analysis. 
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permitted Hamilton to include the DQ-alpha frequency in her 

random-match calculation. Keen also asserted that the DQ-alpha 

analysis should not have been used because the amplifications of 

the DNA used for the DQ-alpha analysis were performed separately 

in the laboratory, "giving rise to the potential for sample 

mix-ups or laboratory error." 

 Keen's first argument fails to acknowledge that the vaginal 

cervical sample was separated into two portions, a sperm sample 

and a non-sperm sample. At oral argument, Keen's counsel argued 

that Hamilton failed to conduct the proper tests to separate 

sperm material from the non-sperm material and that based on 

evidence he had obtained from other cases, he was aware that the 

state laboratory improperly performed such tests. It is 

axiomatic that Keen's counsel's alleged knowledge of evidence 

from other cases is wholly irrelevant to the merits of this case. 

 Further, assuming arguendo, that all possible tests were not 

performed to distinguish the sperm material from the non-sperm 

material, ultimately, Hamilton's analysis clearly established 

that her separations were accurate. Hamilton testified that 

after separating the material from the vaginal cervical sample 

she first conducted the DQ-alpha analysis, which resulted in 

findings of identical genotypes at the DQ-alpha locus. She then 

performed the polymarker test, which revealed that the two 

samples differed in all five locations examined in the polymarker 

test. Comparison with analysis of DNA taken from Greer's blood 
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sample allowed Hamilton to determine conclusively that the sperm 

sample was not contributed by Greer, as the genetic profiles did 

not match. Consequently, the evidence supported Hamilton's use 

of the DQ-alpha analysis in her random-match calculation, as the 

polymarker test allowed her to determine that the 3,3 genotype 

was present in the material that was not contributed by Greer, 

e.g., the sperm material. 

 Keen's second argument regarding separate amplification of 

the genetic material was not raised at trial and consequently is 

barred by Rule 5A:18. Assuming, arguendo, that the matter had 

been properly preserved for appeal, it is nevertheless without 

merit. The record indicates that, although the samples used for 

the DQ-alpha and polymarker testing were separately amplified, 

both were obtained from the same extract of the sperm sample. 

Jury Instructions

 In light of the substantial testimony regarding DNA 

evidence, Keen proposed the following six cautionary jury 

instructions pertaining to DNA evidence: 

 A given DNA profile may be shared by two or more people. 

 The random match probability statistic is not the equivalent 

of a statistic that tells the jury the likelihood of whether 

the defendant committed the alleged crimes. 

 The random match probability statistic is the likelihood 

that the DNA profile of a random person in the population 

would match the DNA characteristics that were found in the 

crime scene evidence. 

 An allele is one of two or more alternative forms of a gene. 

 An allele frequency is the proportion of a particular allele 

among the chromosomes carried by individuals in a 
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population. 

 Where the known DNA sample from the defendant matches the 

unknown sample obtained from the crime scene, it does not 

necessarily mean the defendant is the source of the sample 

found at the crime scene. 

The trial court declined to give any of the six instructions and 

consequently the first and fourth of the proposed instructions 

were proffered as refused instructions. 

 Keen argues that because the jury had no prior experience 

with DNA evidence and no exposure to the application of forensic 

DNA, the cautionary jury instructions, containing "generic" 

information applicable "in any case where DNA evidence [was] 

offered," should have been given. Keen further argues that 

"[j]urors cannot perform their legal duty of fully and fairly 

deliberating the evidence if portions of it, i.e., the DNA 

evidence, is not understood by them." 

 The purpose of any jury instruction is to inform the jury of 

the law guiding their deliberations and verdict. See Cooper v. 

Commonwealth, 2 Va. App. 497, 345 S.E.2d 775 (1986). The 

instructions proposed by Keen and rejected by the trial court 

were statements concerning scientific knowledge, not legal 

principle. The substance of the proposed instructions was 

information which was properly imparted to the jury through the 

testimony of expert witnesses. Thus, Keen's proposed 

instructions would have impermissibly commented upon the 

evidence. Levasseur v. Commonwealth, 225 Va. 564, 595, 304 
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S.E.2d 644, 661 (1983). Accordingly, we hold the trial court did 

not err in refusing Keen's proposed instructions. 

 Holding that the trial court's error in denying Keen's 

discovery request was harmless, that the random-match frequency 

was properly calculated using the DQ-Alpha analysis, and that the 

trial court did not err in refusing Keen's proffered 

instructions, we affirm. 

 Affirmed.