SUPREME COURT OF ARIZONA
STATE OF ARIZONA,
BOBBY LEE TANKERSLEY,
O P I N I O N
Appeal from the Superior Court of Yuma County
The Honorable Thomas A. Thode
Grant Woods, Attorney General
By Paul J. McMurdie, Chief Counsel, Criminal Appeals
Christopher E. Avery, Assistant Attorney General
Attorneys for Appellee
Richard D. Engler
M. Josephine Sotelo, Chief Deputy
Yuma County Public Defender
Attorneys for Appellant
Z L A K E T, Chief Justice.
On November 18, 1991, police discovered the body of 65-
year-old Thelma Younkin in her room at Yuma's Post Park Motel. She
had been strangled, most likely by means of the oxygen tube she
regularly used to assist her breathing. There were bite marks on her breasts and face, her right earlobe had been bitten off, and a
tooth was discovered beneath the body.
The victim's vaginal area
was extensively bruised and lacerated
, and the medical examiner
detected evidence of semen. Fecal matter was found on her legs,
around the bathroom sink, and on a washcloth. DNA EVIDENCE
Defendant Bobby Lee Tankersley became a suspect early in
the investigation. He lived at the same motel and was seen
entering Thelma's room on the night of the murder. Police learned
that the defendant had argued earlier that day with the victim's
daughter, who warned him to leave her family alone. He allegedly
replied, "I will get you before you get me." Immediately following
discovery of the body, a police officer observed that the defendant
was "rather buoyant and exhibiting laughter and exuberant
behavior." He "was in a party mood" and "seemed to be nervous,
pacing back and forth" -- conduct that the officer considered
"inappropriate for the circumstances."
DNA (deoxyribonucleic acid) analysis established that
Tankersley could not be eliminated as the source of a hair
recovered from fecal matter on the sink. Additionally, a forensic
odontologist testified it was "highly probable" that defendant had
bitten the victim's left breast, and another said that his teeth
"matched" the bite marks. Saliva with H antigens, of which the
defendant is a secretor, was found in the bite wounds.
Following a jury trial, Tankersley was convicted of first degree murder and sexual assault. The trial judge sentenced him to
death for the homicide and to a consecutive aggravated term for the
assault. Defendant appeals from both convictions and sentences.
We have jurisdiction pursuant to Ariz. Const. art. VI, § 5(3);
A.R.S. § 13-4031; Ariz. R. Crim. P.
26.15 and 31.2(b).
Defendant challenges the admission of DNA evidence
derived from polymerase chain reaction (PCR) testing. He does not
attack the scientific theory of PCR, but rather its application to
crime scene evidence. Defendant also asserts that the techniques
and procedures used by the lab in this case are not generally
accepted as capable of producing valid, reliable results. Finally,
he questions whether the prosecution laid a proper foundation for
PCR differs significantly from restriction fragment
length polymorphis (RFLP), the technique approved in State v.
Bible, 175 Ariz. 549, 577 & n.17, 858 P.2d 1152, 1180 & n.17
(1993), and used in
State v. Boles, 188 Ariz. 129, 131-32, 933 P.2d
1197, 1199-2000 (1997)
; State v. Hummert, 188 Ariz. 119, 122-24,
933 P.2d 1187, 1190-92 (1997); and
State v. Johnson, 186 Ariz. 329,
330, 922 P.2d 294, 295 (1996)
. Its admissibility is an issue of
first impression for this court. A detailed description of the PCR
technique can be found in George F. Sensabaugh & Cecilia von
Beroldingen, The Polymerase Chain Reaction: Application to the Analysis of Biological Evidence, in Forensic DNA Technology 63-82
(Mark A. Farley & James J. Harrington eds. 1991). See also Kary B.
Mullis, The Unusual Origin of the Polymerase Chain Reaction, Sci.
Am., Apr. 1990, at 56. We attempt only a brief overview here to
provide a foundation for our legal analysis.
PCR is a process for reproducing a short segment of DNA
millions of times, making it
possible to analyze minute or degraded
National Research Council, The Evaluation of Forensic DNA
Evidence 69-70 (1996) [hereinafter 1996 NRC Report]. First, the
extracted DNA is combined with a mixture of polymerase and "all of
the building blocks necessary for DNA replication." Kamrin T.
MacKnight, The Polymerase Chain Reaction (PCR): The Second
Generation of DNA Analysis Methods Takes the Stand, 9 Santa Clara
Computer & High Tech. L.J. 287, 305 (1993). The product is then
heated in a "thermal cycler," which causes the double-stranded DNA
to separate (denature) into two single strands (like splitting a
ladder down the middle). Id.; see also Thomas M. Fleming,
Annotation, Admissibility of DNA Identification Evidence, 84 A.L.R.
4th 313, 319 (1991). When the solution cools, primersSee footnote 1 bind (anneal) to complementary base sequencesSee footnote 2 on the single-stranded
Sensabaugh & Von Beroldingen, supra, at 64.
polymerase starts the synthesis of new DNA strands (extension) by
assembling nucleotideSee footnote 3 building blocks that are complementary to
the template strands. MacKnight, supra, at 305. As a result, two
double-stranded segments of DNA, identical to the original, are
created. The process is repeated, and with each new cycle, the DNA
doubles in size.
Sensabaugh & Von Beroldingen, supra, at 64.
a sufficient amount of the targeted DNA has been produced, a
profile or typing can be done. Id. at 66.
PCR is only an amplification process and does not
directly analyze DNA. To do that, a genetic marker typing test
must be used. Id. The test employed in the present case was the
AmpliType DQ-alpha kit by Cetus Corporation. This kit, in
analyzing the DQ-alpha gene, had the capability of detecting six
alleles, termed 1.1, 1.2, 1.3, 2, 3, and 4. P. Sean Walsh et al.,
Report of the Blind Trial of the Cetus AmpliType HLA Dq. Forensic
Deoxyribonucleic Acid (DNA) Amplification and Typing Kit, 36 J. Forensic Sci. 1551, 1552 (1991).
Each individual has two alleles
that are either the same (e.g., 1.2, 1.2) or different (e.g., 1.2,
4). See People v. Lee, 537 N.W.2d 233, 250 (Mich. App. 1995),
appeal denied, 554 N.W.2d 12 (Mich. 1996).
To identify a specimen's DQ-alpha profile, short DNA
segments that detect specific alleles, called "probes," are fixed
to a nylon membrane at a particular location. 1996 NRC Report,
supra, at 71-72; see also Scientific Evidence, supra, at 327 (for
definition of probe). The amplified DNA is again denatured and
then flooded over the membrane. A chemical reaction occurs
wherever the sample DNA finds its complementary probe, causing a
blue dot to appear at that location. The positions of the dots
indicate the specimen's DQ-alpha genotype. MacKnight, supra, at
306-07. This procedure is known as "reverse dot blotting."
National Research Council, DNA Technology and Forensic Science 42
(1992) [hereinafter 1992 NRC Report].
Once this genotype is determined, it is compared to the
DNA profile of the crime suspect. If the two are different, the
person is excluded. If they "match," then the suspect is a
possible source of the specimen, and questions arise regarding
frequency of the genotype in the population.
In this case, hairs found on the bathroom sink and on a
washcloth, as well as blood samples from the defendant and the
victim, were sent to Forensic Science Associates (FSA) for PCR DQ-
alpha testing. Of the hair samples, only a single strand had
sufficient root material from which DNA could be extracted.
Testing revealed that defendant's genotype was 1.1, 2, while the
victim's was 2, 4. The lab then determined that the hair's profile
was 1.1, 2, thus eliminating the victim as a source but not
excluding the defendant. Dr. Edward Blake, who owns and operates
FSA, testified that 1.1, 2 occurs in about four percent of the
Before trial, the court conducted an extensive Frye
hearing, admitting more than eighty publications on PCR technology.
The state called two witnesses: Dr. Blake and Dr. Helentjaris, a
plant DNA expert at the University of Arizona. Three defense
experts, Drs. Grunbaum, Gerdes, and Riley, testified about PCR
analysis, FSA's laboratory procedures, and the testing done in this
case. At the close of the hearing, the court found that the DNA
evidence was admissible, stating that the defense's real complaint
was of "dirty test tubes," not reliability of the methodology. In
the trial court's view, any problem with FSA's procedures could be
explained to the jury, which would then assess its impact.
Standard for Admissibility of New Scientific Evidence
Although not raised below, the state asks this court to
abandon the Frye test in favor of the current federal standard for
determining the admissibility of new scientific evidence. See
Daubert v. Merrell Dow Pharmaceuticals, 509 U.S. 579, 589, 113 S. Ct. 2786, 2793 (1993) (holding that United States v. Frye, 293 F.
1013 (D.C. Cir. 1923), was superseded by the Federal Rules of
Evidence). We decline to do so. In Johnson, 186 Ariz. at 331, 922
P.2d at 296, we reaffirmed our adherence to Frye. See also Bible,
175 Ariz. at 578-80, 858 P.2d at 1181-83. Moreover, in light of
the prosecution's failure below to request application of the
Daubert decision, the issue is not properly before us.
The state also argues that if Frye is preserved, it
should govern only general principles such as "the variability of
human DNA and its replication via a polymerase chain reaction," not
the forensic application of PCR or specific techniques used in
implementing this technology. We disagree. The following excerpt
from the National Research Council's 1992 report is instructive:
"DNA typing" is a catch-all term for a wide range of
methods for studying genetic variations. Each method has
its own advantages and limitations, and each is at a
different state of technical development. Each DNA
typing method involves three steps:
1. Laboratory analysis of samples to determine
their genetic-marker types at multiple sites of potential
2. Comparison of the genetic-marker types of the
samples to determine whether the types match and thus
whether the samples could have come from the same source.
3. If the types match, statistical analysis of the
population frequency of the types to determine the
probability that such a match might have been observed by
chance in a comparison of samples from different persons.
Before any particular DNA typing method is used for
forensic purposes, it is essential that precise and
scientifically reliable procedures be established for
performing all three steps. . . .
There is no scientific dispute about the validity of
the general principles underlying DNA typing: scientists
agree that DNA varies substantially among humans, that
variation can be detected in the laboratory, and that DNA
comparison can provide a basis for distinguishing samples
from different persons. However, a given DNA typing
method might or might not be scientifically appropriate
for forensic use. Before a method can be accepted as
valid for forensic use, it must be rigorously
characterized in both research and forensic settings to
determine the circumstances under which it will and will
not yield reliable results. It is meaningless to speak
of the reliability of DNA typing in general--i.e.,
without specifying a particular method.
1992 NRC Report, supra, at 51 (emphasis added). Arizona's
application of Frye has historically required general acceptance of
both a scientific principle and the technique applying it. See
State v. Superior Court, 149 Ariz. 269, 277, 718 P.2d 171, 179
Bible, 175 Ariz. at 581-82, 858 P.2d at 1184-85 (finding
general acceptance of Cellmark's procedures for declaring an RFLP
. We see no reason to depart from this approach.DISCOVERY ISSUE
In the present case, PCR amplification and DQ-alpha
testing must each be generally accepted as capable of producing
valid, reliable results. We review the trial court's Frye findings
de novo. Bible, 175 Ariz. at 578, 858 P.2d at 1181.
PCR DQ-Alpha Analysis of Crime Scene Samples
Defendant concedes that PCR DQ-alpha analysis is accepted
as reliable for medical and biological research in the general
scientific community. He says, however, that the same is not true
of its application to crime scene evidence. He claims that PCR
testing in this context is inherently unreliable because the samples are often recovered under imperfect conditions. As a
result, contaminated DNA may be inadvertently amplified, completely
masking the specimen's true DNA. Such contamination could come
from the victim, bystanders, the analyst, or amplified DNA
previously processed within the lab. See 1992 NRC Report, supra,
at 65-67 (discussing possible sources of contamination). All of
the defendant's experts testified that PCR DQ-alpha testing is
inappropriate for crime scene analysis.
The state, however, presented significant evidence to the
contrary. This included reports of blind testing and proficiency
exams, as well as scientific articles describing accurate typing of
mixed samples and degraded specimens. See, e.g.,
Walsh, supra, at
1554; MacKnight, supra, at 344-48.
See also Catherine Theisen
Comey et al., PCR Amplification and Typing of the HLA Dq. Gene in
Forensic Samples, 38 J. Forensic Sci. 239 (1993);
Comey & Bruce Budowle, Validation Studies on the Analysis of the
HLA Dq. Locus Using the Polymerase Chain Reaction, 36 J. Forensic
Sci. 1633 (1991).
The Frye test does not require unanimity among
scientists. State v. Velasco, 165 Ariz. 480, 486, 799 P.2d 821,
827 (1990). It is true that contamination is of particular concern
in any procedure that uses PCR. See 1996 NRC Report, supra, at 71
("The amplification process is so efficient that a few stray
molecules of contaminating DNA can be amplified along with the intended DNA."). This risk, however, has not rendered PCR-based
techniques unacceptable by the scientific community. In fact,
erroneous amplification is far more likely to result in the false
exclusion, not inclusion, of a suspect. Id. Moreover, the
possibility of contamination "may present an open field for cross-
examination." State v. Lyons, 924 P.2d 802, 813 (Or. 1996); see
also People v. Pope, 672 N.E.2d 1321, 1326 (Ill. App. Ct. 1996),
appeal denied, 677 N.E.2d 970 (Ill. 1997). The overwhelming
consensus among scientists is that so long as proper procedures are
followed, the results should be reliable. 1996 NRC Report, supra,
at 23; 1992 NRC Report, supra, at 145-46. See also State v.
Moeller, 548 N.W.2d 465, 482-83 (S.D. 1996); Lee, 537 N.W.2d at
Numerous other courts have found PCR DQ-alpha analysis
admissible under the Frye standard. See Seritt v. State, 647 So.
2d 1, 4 (Ala. Crim. App. 1994); Harmon v. State, 908 P.2d 434, 442
(Alaska Ct. App. 1995); People v. Morganti, 50 Cal. Rptr. 2d 837,
853 (Cal. Ct. App. 1996); Pope, 672 N.E.2d at 1327; State v. Hill,
895 P.2d 1238, 1247 (Kan. 1995); Lee, 537 N.W.2d at 257; State v.
Williams, 599 A.2d 960, 968 (N.J. Super. Ct. Law Div. 1991); State
v. Russell, 882 P.2d 747, 768 (Wash. 1994). We agree with the
trial court here that PCR technology is generally accepted within
the relevant scientific community for use on crime scene evidence.
Furthermore, we observe that the DQ-alpha marker system is a generally accepted means of distinguishing DNA. See Russell, 882
P.2d at 768.
FSA's Techniques and Procedures
Defendant argues that FSA's procedures for amplifying and
analyzing the DQ-alpha gene are not generally accepted. He points
to an array of allegedly improper practices: a lack of written
protocols and current proficiency testing, an excessive number of
cycles run on the thermal cycler, temperature regulation problems,
the failure to quantify the sample's DNA before amplification, and
the reporting of results despite evidence of contamination.
We note at the outset that most of defendant's claims
challenge FSA's implementation of PCR DQ-alpha testing, not the
validity or reliability of the technique itself. Because such
questions relate to the correctness of procedures followed in a
given case, and hence the reliability of particular results, they
are foundational considerations governed by ordinary evidentiary
standards. See State ex rel. Collins v. Superior Court, 132 Ariz.
180, 196, 644 P.2d 1266, 1282 (1982) (Once Frye is satisfied,
scientific evidence is admissible "subject to a foundational
showing that the expert was qualified, the technique was properly
used, and the results were accurately recorded."); Ariz. R. Evid.
702, 703 & 403
; see also 1992 NRC Report, supra, at 23 ("The
adequacy of the method used to acquire and analyze samples in a
given case bears on the admissibility of the evidence and should, unless stipulated by opposing parties, be adjudicated case by
case."). If, for example, testing procedures are so seriously
flawed that the results are rendered unreliable, the trial court
should not admit the evidence. See Russell, 882 P.2d at 766-67.
Once an adequate foundation is established, however, complaints of
laboratory error or incompetence are considered by the trier of
fact in assessing the weight of the evidence. See, e.g., State v.
Murray, 184 Ariz. 9, 30, 906 P.2d 542, 563 (1995) (expert's failure
to follow FBI procedures in preserving and analyzing footprint
evidence goes to weight rather than admissibility); State v. Moore,
885 P.2d 457, 471-75 (Mont. 1994)
, disapproved on other grounds by
State v. Gollehon, 906 P.2d 697, 700-01 (Mont. 1995)
Defendant suggests that strict compliance with guidelines
developed by the Technical Working Group on DNA Analysis and
Methods (TWGDAM) should be a prerequisite for admitting any lab's
test results. He relies heavily on the NRC's recommendation that
laboratories adhere to TWGDAM standards. See 1992 NRC Report,
supra, at 98-99. While we agree that such conformity might aid
trial courts in determining whether an adequate foundational
showing has been made, these guidelines are not mandatory. See id.
at 99. Similarly, certification by the Laboratory Accreditation
Board of the American Association of Crime Laboratory Directors
could arguably provide a useful gauge of reliability, see 1996 NRC
Report, supra, at 77, but it is not required. The appropriate inquiry is whether a lab's techniques have deviated so far from
generally accepted practices that the test results cannot be
accepted as reliable.
In this case, the prosecution presented its foundational
evidence during the Frye hearing. See Bible, 175 Ariz. at 581, 858
P.2d at 1184 (trial court has discretion in deciding whether
foundational showing is to be made outside jury's presence). The
court found all of the expert witnesses qualified and determined
that the test in question complied sufficiently with the protocols
of FSA, other labs, and the kit's manufacturer, Cetus. The judge
also concluded that Dr. Blake had recorded the results. These
factual findings will not be disturbed absent an abuse of
discretion. See State v. Gentry, 888 P.2d 1105, 1118 (Wash. 1995).
As discussed below, we find that the trial judge did not abuse his
discretion in admitting the test results. See also
Hill, 895 P.2d
at 1246-47 (approving FSA's methods
Lee, 537 N.W.2d at 258
State v. Dishon, 687 A.2d 1074, 1087 (N.J. Super. Ct. App.
Div. 1997) (same), certification denied, 693 A.2d 112 (N.J. 1997);
Moeller, 548 N.W.2d at 483-84 (same).
Protocols and Proficiency Testing
FSA's protocols for quality assurance, decontamination,
and evaluation of results were not written out as recommended by
the TWGDAM. Defendant claims that this omission prevented other
scientists from reviewing the lab's methodology. At the Frye hearing, however, Dr. Blake detailed the procedures that he and his
assistant followed in conducting the analysis and controlling for
contamination. Moreover, although TWGDAM guidelines advocate
annual proficiency testing, the fact that FSA had not participated
in such a test for more than two years does not necessarily render
its results unreliable, as the defendant asserts. See 1996 NRC
Report, supra, at 185 ("[P]roficiency-testing . . . bears on the
weight that should be accorded forensic test results.").
Defendant's experts were free to challenge FSA's techniques.
Number of Amplification Cycles
Defendant alleges that FSA's use of thirty-five
amplification cycles in the thermal cycler departs significantly
from generally accepted practices and renders the results
unreliable. He points to the Cetus User Guide and protocols from
several other labs, all of which advocate thirty-two. We cannot
say that the use of thirty-five cycles is a deviation that should
have precluded admission of the data. See 1996 NRC Report, supra,
at 69 ("This [PCR] three-step cycle is repeated, usually 20-35
Temperature During Denaturation
Regulation of the temperature within the thermal cycler
is critical for successful amplification. FSA's calibration
records revealed prior instances in which temperatures had
fluctuated outside of recommended ranges. Defendant, however, makes no claim that this occurred here. Past difficulties with the
thermal cycler are issues that affect weight, not admissibility.
See Moore, 885 P.2d at 471-72.
Quantification of DNA
Defendant challenges FSA's failure to quantify the
extracted DNA prior to amplifying it. Most scientists agree that
quantification should be done to ensure that a sufficient amount of
DNA is available for testing. Dr. Blake testified that although he
normally quantifies before amplification, he does not do so on DNA
extracted from a single hair. This is because the measuring
process would consume half of the sample, leaving nothing for
repeat testing, which is itself an important safeguard. See id. at
In our view, the failure to quantify did not render the
During amplification, FSA used numerous controls to test
for contamination. One of them, a sample run without any added
DNA, showed a faint blue dot. Defendant argues that the final
results should not have been admitted because this was evidence of
contamination. He points to several other labs' protocols, which
state that testing should be considered inconclusive if a control
appears positive. Dr. Blake, however, testified that what appeared
here was "a barely detectable trace material that is too weak to
clearly type." In his view, it was not significant since all of the other controls were negative. Dr. Helentjaris agreed, stating
that the faint dot "wouldn't be evaluated by somebody in the field
. . . as a positive result." Rather, it was "simply a trace
signal." At the conclusion of the hearing, the trial court found
that there was "no sufficient showing of contamination." This
finding is amply supported by the record. The court did not abuse
The defense requested FSA's typing strip photos and
amplification sheets for tests run immediately before and after
those in this case. This material was necessary, defendant
claimed, to fully evaluate possible contamination in Dr. Blake's
lab. He later expanded the request to include every DQ-alpha case
analyzed by FSA that had been incorporated into its population
database, contending that if there had been contamination in any of
those tests, Dr. Blake's frequencies would be flawed.
After extensive briefing and oral argument, the trial
judge denied the defendant's discovery motion. He found that the
request was burdensome and irrelevant since FSA's samples
contributed to only one portion of the entire database used by Dr.
Blake when calculating the frequencies. Moreover, based on
evidence presented during the Frye hearing, the trial court noted
that Dr. Blake's population data compared favorably to frequencies
that would be expected under an assumption of Hardy-Weinberg equilibrium.See footnote 4
In an effort to establish substantial need for the raw
data, the defense also asserted "lack of veracity" in Dr. Blake's
previous reporting. The court, however, found no basis for this
contention. We review the court's ruling for an abuse of
discretion. See State v. Piper, 113 Ariz. 390, 392, 555 P.2d 636,
638 (1976); Ariz. R. Crim. P.
To warrant disclosure, the defendant must show both
"substantial need" for the requested information and that he "is
unable without undue hardship to obtain the substantial equivalent
by other means." Id. The trial court may consider if compliance
with a discovery order "would be unreasonable or oppressive." Id.
Here, each side presented a very different picture of the
consequences of disclosure. The state claimed that compliance with
defendant's request would be extremely burdensome, taking over 500
hours to complete and causing Dr. Blake to close down his
laboratory. Defense counsel, on the other hand, contended that she
had been to the lab and would need less than a day to copy
everything that she had seen. Alternatively, she suggested that a
defense expert could be appointed to conduct an in-house review during which selected documents would be copied.
Likewise, each side had its own version of the material's
availability elsewhere. The state believed that the defense had
access to this information from other sources, including published
data and documents previously received from various laboratories.
Defendant, however, argued that the disclosure from other labs
related to RFLP, not PCR. Furthermore, the publications would not
be sufficient because Dr. Blake had extensively added to his
database after the studies were released.
We note that the 1992 NRC Report emphasizes the
importance of complete and open disclosure. See 1992 NRC Report,
supra, at 132, 148 ("All materials relied on by prosecution experts
must be available to defense experts, and vice versa. . . .
Protective orders should not be used to prevent experts on either
side from obtaining all relevant information, which can include
original materials, data sheets, software protocols, and
information about unpublished databanks."). Similarly, there are
no scientific grounds for withholding information in the discovery
process. 1996 NRC Report, supra, at 167. Nevertheless, the trial
judge was in the best position to rule on the defendant's request
and had the discretion to do so. "Something is discretionary
because it is based on an assessment of conflicting procedural,
factual or equitable considerations which vary from case to case
and which can be better determined or resolved by the trial judge, who has a more immediate grasp of all the facts of the case, an
opportunity to see the parties, lawyers and witnesses, and who can
better assess the impact of what occurs before him." State v.
Chapple, 135 Ariz. 281, 297 n.18, 660 P.2d 1208, 1224 n.18 (1983).
In the present case, almost four months had passed
between defendant's initial discovery request and the court's final
ruling on the matter. During this time, the trial judge heard and
considered arguments from both sides. He ultimately determined
that the defendant had not met the requirements of Rule 15.1(e),
and consequently was not entitled to the material that he sought.
We cannot say that the judge abused his discretion.
EVIDENCE OF ALTERNATIVE SUSPECTS
Defendant claims it was error to exclude evidence that
Kenneth Tyman may have committed the murder. He sought to
introduce the following: (1) that Tyman had previously rented the
room later occupied by the victim and was seen with a key to that
room weeks after the murder (which he denied); (2) that he lived
near the motel in a tent where female undergarments soiled with
feces had been found; (3) that he had been convicted of sexual
assault more than ten years prior to the murder, was required to
register as a convicted sex offender, had seen a psychologist
concerning sex problems, and possessed pornographic materials after
the murder; and (4) that there was circumstantial evidence linking Tyman to the murder of his wife, who had been strangled in Show Low
two years earlier and was about the same age as the victim here.
The trial court admitted evidence regarding the room key and the
stained underwear, but excluded Tyman's sexual history and the Show
Low murder based on Arizona Rules of Evidence 403 and 404(b). We
review the admission or exclusion of evidence for abuse of
discretion. State v. Robinson, 165 Ariz. 51, 56, 796 P.2d 853, 858
A defendant is permitted to show that another person
committed the crime for which he was charged. State v. Oliver, 169
Ariz. 589, 590, 821 P.2d 250, 251 (App. 1991). It is, however,
within the trial court's sound discretion to exclude such evidence
if "it simply affords a possible ground of suspicion against
another." Id. at 591, 821 P.2d at 252. To gain admission, "[t]he
defendant must show that the evidence has an inherent tendency to
connect the other person with the actual commission of the crime."
Rule 404(b) creates an exception to the ban on character
evidence when "other crimes, wrongs, or acts" are offered for a
relevant purpose other than propensity. State v. Hughes, 189 Ariz.
62, 68, 938 P.2d 457, 463 (1997). This rule applies to other acts
of third persons as well as to those of defendants. See United
States v. McCourt, 925 F.2d 1229, 1236 (9th Cir. 1991).
The defense asserts that the Show Low incident was offered to suggest that Tyman, not defendant, murdered the victim
in this case. "To establish identity based on other acts, 'the
modus operandi of and the circumstances surrounding the two crimes
must be sufficiently similar as to be like a signature.'" Hughes,
189 Ariz. at 68, 938 P.2d at 463 (quoting State v. Jackson, 186
Ariz. 20, 27, 918 P.2d 1038, 1045 (1996), cert. denied, 117 S. Ct.
527 (1996)). Although the details need not be identical, there
must be similarities between important aspects where one would
normally expect to find differences. See State v. Roscoe, 145
Ariz. 212, 217, 700 P.2d 1312, 1317 (1984). Even if we assume that
it was Tyman who committed the Show Low murder, the parallels
between the two crimes are not "sufficiently similar as to be like
a signature." The only likenesses we can ascertain are that both
victims were strangled and were approximately the same age. This
is not enough. See Hughes, 189 Ariz. at 68, 938 P.2d at 463
(concluding insufficient similarities where both victims were women
who had angered defendant, and the same person may have been paid
to commit the crimes); cf. State v. Harding, 137 Ariz. 278, 289-90,
670 P.2d 383, 394-95 (1983) (finding striking similarities where
both victims had stayed at hotels, were similarly hog-tied and
gagged, and had personal items and vehicles stolen). Moreover,
there are notable differences between the two crimes. Unlike the
present case, the Show Low murder included no evidence of ligature
strangulation, bite marks, or sexual assault. See State v. Stuard, 176 Ariz. 589, 597-98, 863 P.2d 881, 889-90 (1993) (examining
differences as well as similarities among the crimes).
Even if we assume, arguendo, that the evidence would be
admissible under Rule 404(b), it may nevertheless "be excluded if
its probative value is substantially outweighed by the danger of
unfair prejudice, confusion of the issues, or misleading the jury,
or by considerations of undue delay, waste of time, or needless
presentation of cumulative evidence." Ariz. R. Evid.
United States v. Perkins, 937 F.2d 1397, 1401 (9th Cir. 1991).
Charges were never brought against Tyman for the Show Low murder.
Thus, any discussion of it would likely have resulted in a trial
within a trial. Under such circumstances, the minimal probative
value of the evidence was substantially outweighed by its potential
for unfair prejudice, jury confusion, and unnecessary delay. The
trial judge's ruling under Rule 403 was not a clear abuse of
discretion. See Williams, 133 Ariz. at 231, 650 P.2d at 1213.
The trial court also excluded Tyman's ten-year-old sexual
assault conviction and evidence of his alleged "perverse sexual
propensities." The judge found that the conviction was too remote
in time and not sufficiently similar to the instant crime to be
relevant.See footnote 5 We agree. Tyman's conviction was for molesting his own daughters. Any similarity between that conduct and the assault in
the present case is tenuous at best. More importantly, ten years
is too distant in time to be of much probative value. See Roscoe,
145 Ariz. at 217, 700 P.2d at 1317.
Finally, evidence presented at trial established that
Tyman had no teeth and that his dentures had been destroyed in a
fire years before the murder. Expert testimony demonstrated that
the bite marks found on the victim's body could not have been made
by someone without teeth or with dentures. For all of the
foregoing reasons, we conclude the trial court was correct in
excluding alternative suspect evidence involving Kenneth Tyman.
Defendant argues that it was error to exclude evidence of
alternative suspect Torii Thompson. Apparently, Thompson had sued
the victim, Thelma Younkin, for $50 in small claims court. He also
had an unsatisfied judgment against a Christine Bauer for $2,000.
Shortly after the Younkin murder, Thompson sent a letter to Bauer
that stated, "Christine, this is the year for me to settle up with
all who have fucked over me. See you soon, Torii." A newsclipping
of the Younkin murder and a copy of the lawsuit that Thompson had
filed against Younkin were attached to the letter. Because
Thompson was unavailable -- neither the defense nor the state could
locate him -- defendant wanted Bauer to testify regarding the
letter as a statement against Thompson's penal interest. See Ariz. R. Evid.
The trial judge excluded this evidence,
finding that there was nothing to corroborate the trustworthiness
of the implied admission that Thompson killed Younkin. The court
further noted that the statement was made with a monetary interest,
which weighed against its reliability.
We clarified the requirements of Rule 804(b)(3) in State
v. LaGrand, 153 Ariz. 21, 26-29, 734 P.2d 563, 568-71 (1987). For
a statement to be admissible under the rule, the declarant must be
unavailable, the statement must be against the declarant's
interest, and there must be corroborating circumstances that
"clearly indicate the trustworthiness of the exculpatory
statement." Id. Many factors are involved in determining
trustworthiness, including: the existence of supporting and
contradictory evidence, the relationship between the declarant and
the listener, the relationship between the declarant and the
defendant, the number of times the statement was made, the length
of time between the event and the statement, the psychological and
physical environment at the time of the statement, and whether the
declarant would benefit from the statement. See id. at 27-28, 734
P.2d at 569-70.
The first requirement of admissibility, that the
declarant be unavailable, is met here. Likewise, the second
qualification, that the statement be against the declarant's
interest, is satisfied. The rule does not require a direct confession of guilt. See id. at 27, 734 P.2d at 569. "'Rather, by
referring to statements that "tend" to subject the declarant to
criminal liability, the Rule encompasses disserving statements by
a declarant that would have probative value in a trial against the
declarant.'" Id. (quoting United States v. Thomas, 571 F.2d 285,
288 (5th Cir. 1978)). In the present case, Thompson did not make
a direct confession of guilt. Instead, his letter to Bauer
suggested that he killed Younkin. Because this implied statement
would tend to subject Thompson to criminal liability, it meets the
The corroborating evidence requirement, however, is not
satisfied. No further evidence links Thompson to the Younkin
murder. On the other hand, there is ample contradictory evidence,
for example, the eye-witness who saw defendant enter Younkin's
room, the DNA evidence, the bite-mark evidence, and the absence of
any witness placing Thompson near the area. The statement was made
only once. See id. at
28, 734 P.2d at 570 ("The number of times
the statement is made and the consistency of multiple statements
may assist in determining trustworthiness.").
Thompson likely made it as an attempt to collect on a debt. That
he would benefit from the statement makes it less reliable. See
id. We agree with the trial judge that this evidence did not meet
the requirements of Rule 804(b)(3). There was no abuse of
discretion in excluding it.
On appeal, the defendant argues that the Show Low
material is admissible as a public record. See Ariz. R. Evid.
Because he did not assert this argument in the trial
court, however, the issue is waived. See McCormick on Evidence §
51, at 199 n.17 (4th ed. 1992) ("[I]f a specific ground for
admission is claimed in the offer of proof but is not applicable
and the judge excludes the evidence, the proponent cannot complain
if there was another ground for admission.").
Defendant challenges the lesser-included jury instruction
approved in State v. Wussler, 139 Ariz. 428, 430, 679 P.2d 74, 76
(1984), which requires jurors to acquit on a charged offense before
considering anything less. He argues that Wussler should be
overruled in favor of a "reasonable efforts" instruction. Such a
change was recently adopted in State v. LeBlanc, 186 Ariz. 437,
438, 924 P.2d 441, 442 (1996). That opinion, however, specifically
held that it would apply only prospectively. Id. at 440, 924 P.2d
at 444. The giving of a Wussler-type instruction here was not
LATE NOTICE OF INTENT TO SEEK THE DEATH PENALTY
The state notified defendant of its intent to seek the
death penalty one day late. See Ariz. R. Crim. P.
(requiring notice within 30 days of arraignment). Defendant claims
that this delay deprived the trial court of jurisdiction to impose a capital sentence. We have held otherwise. Barrs v. Wilkinson,
186 Ariz. 514, 515, 924 P.2d 1033, 1034 (1996); Jackson, 186 Ariz.
at 24, 918 P.2d at 1042.
Defendant raises no sentencing issues. Nevertheless, we
must independently review the aggravating and mitigating factors to
determine if death is an appropriate penalty. See A.R.S. § 13-
The trial judge found that the murder was committed in an
especially heinous, cruel, or depraved manner. A.R.S. § 13-
703(F)(6). In finding both prongs of this aggravating factor, the
court observed the following:
We agree that this murder was committed in an especially heinous and depraved manner. The victim was clearly helpless, the
killing was senseless, and there is evidence of both needless
mutilation to the victim's body and gratuitous violence. See State
v. Gretzler, 135 Ariz. 42, 52, 659 P.2d 1, 11 (1983). We thus
uphold the (F)(6) aggravating factor on this basis and need not
determine whether cruelty also exists. See State v. West, 176
Ariz. 432, 448, 862 P.2d 192, 208 (1993).
The defendant was a healthy male of good physical
ability and strength, while the victim was an aged
female, ill and infirm, of gentle disposition, and wholly
at his mercy.
The victim was strangled, apparently by her own
oxygen tubes, and suffered a painful and frightening
The victim was physically and sexually assaulted by
the defendant while still alive or while at the point of
The defendant chewed off parts of the victim's flesh
while the victim was still alive.
The victim suffered great pain inflicted by the
The defendant caused feces to be smeared on the
The defendant bit and chewed the victim's living
flesh repeated times.
The victim offered no threat, meanness, or harm to
the defendant and offered only the neighborly friendship
of a frail, little old lady.
In mitigation, the trial court found that, even though
the defendant's alcohol intoxication on the night of the murder may
have caused some degree of impairment, his ability to appreciate
the wrongfulness of his conduct or to conform his conduct to the
law's requirements was not significantly impaired. See A.R.S. §
13-703(G)(1). The court also considered evidence of defendant's
history of substance abuse, good behavior during previous
incarcerations, loving relationships with some family members,
potential for rehabilitation, and dysfunctional upbringing. In
conducting our independent review, we find, as did the trial judge,
that the proven mitigation is not sufficiently substantial to call
Defendant's convictions and sentences are affirmed.
THOMAS A. ZLAKET, Chief Justice
STANLEY G. FELDMAN, Justice
JAMES MOELLER, Justice
FREDERICK J. MARTONE, Justice
EINO M. JACOBSON, Judge (Retired)
Justice Robert J. Corcoran (Retired) did not participate in the
determination of this matter. Pursuant to Ariz. Const. art. VI,
§ 3, the Honorable Eino M. Jacobson, Judge (Retired) of the Arizona
Court of Appeals, Division One, was designated to sit in his stead.
A primer "attaches to one end of a DNA fragment and
provides a point for more complementary nucleotides to attach and
replicate the DNA strand." Federal Judicial Center, Reference
Manual on Scientific Evidence 326 (1994)[hereinafter Scientific
The DNA "ladder" is comprised of molecule pairs called
"bases" -- adenine(A), cytosine(C), guanine(G), and thymine(T).
Fleming, supra, at 319. G and C bind exclusively with each
other, as do A and T. The order of these bases along the DNA
molecule constitutes a genetic code. Mullis, supra, at 56. Each
variation of a specific sequence or gene is called an "allele."
Fleming, supra, at 319; Scientific Evidence, supra, at 323.
A nucleotide is a "unit of DNA consisting of a base (A, C,
G, or T) and attached to a phosphate and a sugar group."
Scientific Evidence, supra, at 326.
The Hardy-Weinberg principle predicts the frequency of a
genotype, assuming a large, randomly-mating population without
selection, migration, and mutation. 1992 NRC Report, supra, at
169. Dr. Blake, the state's expert, testified that it is often
used to check population data for potential problems by comparing
the observed frequencies to those expected under an assumption of
Ariz. R. Evid. 404(c) regarding character evidence in
sexual misconduct cases did not become effective until December
1, 1997, and thus was not applicable at the time of defendant's