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David A. Chami, AZ #027585

PRICE LAW GROUP, APC

8245 N. 85th Way

Scottsdale, AZ 85258

T: (818) 600-5515

F: (818) 600-5415

david@pricelawgroup.com

Haytham Faraj

LAW OFFICES OF HAYTHAM FARAJ

1935 W Belmont Ave.

Chicago, IL 60657

T: (312) 635-0800

F: (202) 280-1039

haytham@farajlaw.com

Attorneys for Plaintiff

IN THE UNITED STATES DISTRICT COURT

FOR THE DISTRICT OF ARIZONA

Mussalina Muhaymin as Personal 

Representative of the Estate of 

Muhammad Abdul Muhaymin Jr., 

Plaintiff,

v.

City of Phoenix, an Arizona Municipal 

Corporation, et al.,

Defendants.

Case No.: CV-17-04565-PHX-SMB

PLAINTIFF’S MOTION TO 

EXCLUDE OPINION TESTIMONY 

BY GARY M. VILKE M.D. AS 

OUTSIDE THE SCOPE OF FED. R. 

EVID. 702 PURSUANT TO DAUBERT

Pursuant to Federal Rules of Evidence 104(a), Plaintiff Mussalina Muhaymin (“Plaintiff” 

or “Ms. Muhaymin”), by and through undersigned counsel, respectfully moves to exclude 

testimony by Gary M. Vilke, M.D. (“Dr. Vilke”) from admission at trial pursuant to Fed. R. 

Evid. 702 and Daubert. In support, Ms. Muhaymin incorporates Plaintiff’s Memorandum below. 
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TABLE OF CONTENTS

I. INTRODUCTION.......................................................................................... 1

II. LEGAL STANDARD..................................................................................... 3

III. ARGUMENT.................................................................................................. 5

A.DR. VILKE IS NOT QUALIFIED TO OPINE AS TO THE CAUSE OF MR. 

MUHAYMIN’S DEATH ............................................................................................ 5

1. Dr. Vilke Has No Independent Qualifications To Make Cause Of Death 

Determinations In Cases Of Unnatural Death ....................................................................... 5

2. Dr. Vilke Does Not Have Enough Specific Scientific Information In This Case 

To Make Determinations Regarding Mr. Muhaymin’s Cause Of Death............................... 7

3. Dr. Vilke’s Own Description Of The Physical Requirements For Positional 

Asphyxia Relies Upon Measurements To Which Dr. Vilke Could Not Possibly Have Had 

Access From Body Camera Footage ..................................................................................... 8

B. THE REPORT FAILS TO IDENTIFY BASES FOR DR. VILKE’S 

CONCLUSIONS ....................................................................................................... 10

C. DR. VILKE’S RESEARCH IS BOTH UNRELIABLE AND INAPPLICABLE TO 

THIS CASE ............................................................................................................... 12

1. Dr. Vilke’s Research Is Irrelevant To This Case .............................................. 12

2. Dr. Vilke’s Research Is Unreliable.................................................................... 15

D.DR. VILKE IS NOT QUALIFIED TO REBUT PLAINTIFF’S 

EXPERT WITNESS.................................................................................................. 16

IV. CONCLUSION............................................................................................. 17
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TABLE OF AUTHORITIES

Cases

Aguilar v. City of Los Angeles, 

No. CV 17-4382-CBM-MRW, 2018 WL 10017349 (C.D. Cal. Oct. 2, 2018) .......................... 7

Apple, Inc. v. Samsung Elecs. Co., 

No. 11-CV-01846-LHK, 2013 WL 5955666 (N.D. Cal. Nov. 6, 2013) .................................... 6

Bourjaily v. United States, 

483 U.S. 171 (1987).................................................................................................................... 5

Brouillette v. Weymouth Shoe Co., 

157 Me. 143, 145 (Me. 1961)..................................................................................................... 8

Claar v. Burlington Northern R. Co., 

29 F.3d 499 (9th Cir. 1994) ...................................................................................................... 17

Daubert v. Merrell Dow Pharm., Inc., 

43 F.3d 1311 (9th Cir. 1995) .............................................................................................passim

Daubert v. Merrell Dow Pharm., Inc., 

509 U.S. 579 (1993)...........................................................................................................passim

Davis v. McKesson Corp., 

No. CV-18-1157-PHX-DGC, 2019 WL 3532179 (D. Ariz. Aug. 2, 2019) ............................. 10

Estate of Lynott by & through Moen v. Luckovich, 

No. C14-0503RSL, 2018 WL 501577 (W.D. Wash. Jan. 22, 2018), reconsideration denied, 

No. C14-0503RSL, 2018 WL 655509 (W.D. Wash. Feb. 1, 2018) ........................................... 6

Gen. Elec. Co. v. Joiner, 

522 U.S. 136 (1997).................................................................................................. 4, 10, 11, 14

Harvey v. State, 

207 So. 2d 108, 118 (Miss. 1968)............................................................................................... 8
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Kumho Tire Co. v. Carmichael, 

526 U.S. 137, 119 S. Ct. 1167, 143 L. Ed. 2d 238 (1999)............................................ 12, 15, 16

Lust By & Through Lust v. Merrell Dow Pharm., Inc., 

89 F.3d 594 (9th Cir. 1996) .............................................................................................. 2, 4, 15

Moussouris v. Microsoft Corp., 

311 F. Supp. 3d 1223 (W.D. Wash. 2018).................................................................................. 7

Parrish v. State,

139 Ala. 16, 36 So. 1012 (1904)................................................................................................. 8

Smith v. Pac. Bell Tel. Co., Inc., 

649 F.Supp.2d 1073 (E.D. Cal. 2009) ........................................................................................ 7

U.S. v. Crumby.............................................................................................................................. 16

United States v. Scop,

846 F.2d 135 (2d Cir. 1988) ....................................................................................................... 8

United States v. W.R. Grace, 

504 F.3d 745 (9th Cir. 2007) ............................................................................................ 4, 6, 13

YKK Corp. v. Jungwoo Zipper Co., 

213 F. Supp. 2d 1195 (C.D. Cal. 2002) ...................................................................................... 6

Rules

Fed. R. Civ. P. 26(a)(2)(B)(i) ......................................................................................................... 4

Fed. R. Evid. 702 ........................................................................................................................ 3, 7
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I. INTRODUCTION

Defendants City of Phoenix, et al. (“Defendants”), retained a Gary M. Vilke, M.D., to 

testify as an expert witness on their behalf at trial. Dr. Vilke’s intended testimony and purported 

opinions are set forth in a seventeen-page report (the “Report”) (attached hereto as Exhibit A), 

his deposition testimony taken on October 30, 2020 (“October Deposition”) (attached hereto as 

Exhibit B) and on November 19, 2020 (“November Deposition”) (attached hereto as Exhibit C), 

and a twelve-page rebuttal report (the “Rebuttal Report) (attached hereto as Exhibit D). (A copy 

of Dr. Vilke’s curriculum vitae is also attached hereto as Exhibit E.)

According to Dr. Vilke’s Report, he was retained to “provide expert opinion [...] on 

whether the actions of the police officers caused or contributed to the cardiac arrest and death of 

Mr. Muhaymin Jr.” Report, p. 1. In reaching his ultimate conclusion, Dr. Vilke’s opines that (1) 

“Mr. Muhaymin’s cardiac arrest was most likely caused by his underlying coronary artery disease 

coupled with an intramuscular left anterior descending coronary artery, methamphetamine use 

and his agitation,” and that (2) the “actions of the officers to control and restrain Mr. Muhaymin 

did not cause or contribute to his cardiac arrest and death.” Report, p. 7.

Dr. Vilke is an emergency room doctor. He is not a pathologist and has had no training in 

conducting autopsies. In his position as an E.R. physician, Dr. Vilke’s vocation and expertise is 

in the area of saving lives. Dr. Vilke is facially unqualified to provide an expert opinion as to the 

cause of Mr. Muhaymin death, as Dr. Vilke’s area of expertise is not in making cause of death 

determinations. Furthermore, and more specifically to this case, Dr. Vilke did not perform an 

autopsy on Mr. Muhaymin. Dr. Vilke did not review any tissue samples. Dr. Vilke did not even 

examine Mr. Muhaymin’s body. Even further, Dr. Vilke’s entire Report and Rebuttal are based 
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on the premise that it was not possible for the officers’ use of weight and position to have caused

Mr. Muhaymin to asphyxiate, but he expressly admits that this premise rests on specific 

calculations of weight and time that he cannot possibly have. Defendants simply cannot show 

that Dr. Vilke possesses the requisite scientific expertise or necessary information to provide an 

educated expert opinion as to the cause of Mr. Muhaymin’s death.

Moreover, although Dr. Vilke is also a self-described “independent researcher on the 

physiologic effects of restraints, weight force and body position,” (Report, p. 1), his purported 

opinions and conclusions are not scientifically supported by his own research, which involved 

studies and publications wherein test subjects were subjected to situations and factors wholly 

dissimilar to the events leading up to Mr. Muhaymin’s death. Simply put, there is a massive 

analytical gap between Dr. Vilke’s unsupportable assumptions in Mr. Muhaymin’s case and the 

“scientific research” that Dr. Vilke relies upon in determining that the officers involved did not 

contribute to Mr. Muhaymin’s death. 

Furthermore, even if his conclusions were supported by his own research – which they are 

not – Dr. Vilke’s research and publications regarding positional asphyxia coincided directly with 

his being retained by municipalities and police forces in cases involving asphyxia. Indeed, for 

the past two decades, Dr. Vilke has regularly and almost exclusively testified on behalf of 

defendants in civil cases alleging wrongful death by asphyxia. This alone is enough to raise 

serious doubt as to the admissibility of Dr. Vilke’s testimony in the Ninth Circuit, which has 

emphasized that “a scientist's normal workplace is the lab or the field, not the courtroom or the

lawyer's office.” Lust By & Through Lust, 89 F.3d at 597.
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Finally, it cannot possibly be shown that Dr. Vilke possesses the scientific expertise or 

information necessary to rebut Ms. Muhaymin’s expert witness, a fully qualified pathologist who, 

unlike Dr. Vilke, personally reviewed tissue samples prior to preparing his report.

Because Dr. Vilke’s purported expert opinions are unsubstantiated by relevant scientific 

data, and because Dr. Vilke goes well beyond his field of actual, vocational expertise, Mr. 

Muhaymin respectfully requests that the Court exclude Dr. Vilke’s report, testimony, and rebuttal 

opinions from trial pursuant to Daubert.

II. LEGAL STANDARD

In order to submit expert testimony to the jury, Defendants must establish that the 

testimony from their expert satisfies the four Rule 702 admissibility criteria: (1) the witness must 

be “qualified as an expert by knowledge, skill, expertise, training, or education”; (2) the 

testimony must be “based upon sufficient facts or data”; (3) the testimony must be “the product 

of reliable principles and methods”; and (4) the witness must “appl[y] the principles and methods 

reliably to the facts of the case.” Fed. R. Evid. 702. An expert’s report and testimony must provide 

the method, facts, and experience relied upon in reaching a conclusion. Daubert v. Merrell Dow 

Pharm., Inc., 509 U.S. 579, 592-593 (1993) (“Daubert I”).

Rule 702 imposes a special gate-keeping obligation upon the Court to ensure that any 

proffered expert testimony is both “reliable” and “relevant.” See Daubert I., 509 U.S. at 589. 

“Under Daubert, [the Court] must engage in a difficult, two-part analysis.” Daubert v. Merrell 

Dow Pharm., Inc., 43 F.3d 1311, 1315 (9th Cir. 1995) (“Daubert II”). “First, [the Court] must 

determine nothing less than whether the experts' testimony reflects “scientific knowledge,” 

whether their findings are “derived by the scientific method,” and whether their work product 
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amounts to “good science.” Id. “Second, [the Court] must ensure that the proposed expert 

testimony is “relevant to the task at hand,” [...] i.e., that it logically advances a material aspect 

of the proposing party's case. Id.

“[S]omething doesn't become ‘scientific knowledge’ just because it's uttered by a scientist; 

nor can an expert's self-serving assertion that his conclusions were ‘derived by the scientific 

method’ be deemed conclusive...” Daubert II, 43 F.3d at 1315–16 (9th Cir. 1995). “[The Court’s] 

task, then, is to analyze not what the experts say, but what basis they have for saying it.” Id. at 

1316. “[T]he party presenting the expert must show that the expert's findings are based on sound 

science...” Id.

The Court is therefore required to engage in a “holistic” analysis of the expert’s testimony. 

See United States v. W.R. Grace, 504 F.3d 745, 762 (9th Cir. 2007). In doing so, the expert’s 

opinion testimony (and report) must be reviewed for “overall sufficiency of the underlying facts 

and data, and the reliability of the methods, as well as the fit of the methods to the facts of the 

case.” Id. If a large analytical gap exists between the data and the opinion proffered, the trial 

court may properly exclude the testimony as unreliable. Gen. Elec. Co. v. Joiner, 522 U.S. 136, 

146 (1997). 

Another “‘very significant fact’ [in determining reliability] is whether the expert has 

‘developed [his] opinions expressly for purposes of testifying,’ since ‘a scientist's normal 

workplace is the lab or the field, not the courtroom or the lawyer's office.’” Lust By & Through 

Lust v. Merrell Dow Pharm., Inc., 89 F.3d 594, 597 (9th Cir. 1996) (quoting Daubert II, 43 F.3d 

at 1317).
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It should be noted that the Supreme Court has described the Court’s gatekeeper role 

regarding expert testimony as especially important because such testimony introduces special 

dangers to the factfinding process. Expert testimony “can be both powerful and quite misleading 

because of the difficulty in evaluating it.” Daubert I, 509 U.S. at 595. Therefore, federal judges 

must exclude proffered scientific evidence under Fed. R. Evid. 702 unless they are convinced 

that it speaks clearly and directly to an issue in dispute in the case, and that it will not mislead 

the jury. Daubert II, 43 F.3d at 1321.

Finally, the proponent of expert testimony has the burden of establishing that the 

admissibility requirements are met by a preponderance of the evidence. See Bourjaily v. United 

States, 483 U.S. 171, 175 (1987).

III. ARGUMENT

A. DR. VILKE IS NOT QUALIFIED TO OPINE AS TO THE CAUSE OF MR. 

MUHAYMIN’S DEATH 

1. Dr. Vilke Has No Independent Qualifications To Make Cause Of Death 

Determinations In Cases Of Unnatural Death.

Dr. Vilke opines that “Mr. Muhaymin’s cardiac arrest was most likely caused by his 

underlying coronary artery disease coupled with an intramuscular left anterior descending 

coronary artery, methamphetamine use and his agitation,” and that the “actions of the officers to 

control and restrain Mr. Muhaymin did not cause or contribute to his cardiac arrest and death.” 

Report, p. 7. In short, Dr. Vilke opines on the cause of Mr. Muhaymin’s death. However, Dr. 

Vilke is not qualified generally to make determinations as to the cause of death, particularly

where the deceased did not die of natural causes. Although Dr. Vilke may have been qualified to 

diagnose Mr. Muhaymin with coronary artery disease had he presented symptoms at the E.R. and 
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appropriate tests were run to verify any initial diagnosis, Dr. Vilke is patently unqualified to 

render an opinion that coronary artery disease, methamphetamine use, or “agitation” caused his 

death.

Dr. Vilke does not specialize in pathology, and in fact has no training in pathology.

November Deposition, p. 7:14-18. Dr. Vilke has never performed an autopsy. Id., at p. 7:19-21. 

In his position as an E.R. physician, Dr. Vilke’s experience with “determining” cause of death is 

almost exclusively limited to the signing of death certificates in which the deceased died of 

natural causes in an emergency room. Id., at pp. 7:22-8:9. In sum, Dr. Vilke’s area of expertise 

is saving lives in an emergency situation, not determining cause of death, and especially not 

determining unnatural causes of death. This area of expertise is exclusively covered by the field 

of pathology, in which, again, Dr. Vilke has no training. 

As multiple Ninth Circuit district courts have noted, “[e]xpert testimony is required to be 

within the scope of the proffered expert's expertise.” YKK Corp. v. Jungwoo Zipper Co., 213 F. 

Supp. 2d 1195, 1203 (C.D. Cal. 2002); See Also W.R. Grace, 455 F. Sup. 2d at 1188; Apple, Inc. 

v. Samsung Elecs. Co., No. 11-CV-01846-LHK, 2013 WL 5955666, at *2 (N.D. Cal. Nov. 6, 

2013); Estate of Lynott by & through Moen v. Luckovich, No. C14-0503RSL, 2018 WL 501577, 

at *2 (W.D. Wash. Jan. 22, 2018), reconsideration denied, No. C14-0503RSL, 2018 WL 655509

(W.D. Wash. Feb. 1, 2018). Dr. Vilke is therefore not qualified to opine to an impressionable 

jury as to the cause of Mr. Muhaymin’s unnatural death, having no training or expertise in 

determining the same.
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2. Dr. Vilke Does Not Have Enough Specific Scientific Information In This Case 

To Make Determinations Regarding Mr. Muhaymin’s Cause Of Death.

Furthermore, even if Dr. Vilke did possess the requisite expertise and training to qualify 

him to determine cause of death in police interactions (he does not), he possesses absolutely none 

of the necessary information to make such a determination. It is undisputed that Dr. Vilke has 

had absolutely no personal contact with Mr. Muhaymin’s body. He did not perform an autopsy, 

nor did he ever even nominally examine the body. Further, Dr. Vilke admits that he never 

reviewed the available brain, heart, and lung tissue samples, either in preparation of his original 

Report or the Rebuttal Report (rebutting Ms. Muhaymin’s expert pathologist who did review the 

tissue samples). November Deposition, p. 73:13-25. 

As an aside, this is not the first time Dr. Vilke has attempted to opine on the cause of death 

in a wrongful death suit without actually examining the decedent’s body. In Aguilar v. City of 

Los Angeles, the Central District of California precluded Dr. Vilke from testifying that the 

existence of controlled substances in the decedent’s body contributed to his death because Dr. 

Vilke “did not examine Decedent, and did not interpret the coroner's toxicology test of 

Decedent...” No. CV 17-4382-CBM-MRW, 2018 WL 10017349, at *1 (C.D. Cal. Oct. 2, 2018).

As has been stressed by district courts throughout the Ninth Circuit, "[r]elevant expert 

testimony is admissible only if an expert knows of facts which enable him to express a reasonably 

accurate conclusion." Moussouris v. Microsoft Corp., 311 F. Supp. 3d 1223, 1244 (W.D. Wash. 

2018) (citing Smith v. Pac. Bell Tel. Co., Inc., 649 F.Supp.2d 1073, 1096 (E.D. Cal. 2009); Fed. 

R. Evid. 702). 
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Dr. Vilke’s determination of the cause of death has no basis in any objective scientific 

testing or observation of Mr. Muhaymin’s body. His entire testimony is based exclusively on his 

perceptions of the video footage. As described in the following section, according to Dr. Vilke’s 

own description of the requirements for positional asphyxia, the information possessed by Dr. 

Vilke is inadequate to enable him to make the determinations he did in his Report.

3. Dr. Vilke’s Own Description Of The Physical Requirements For Positional 

Asphyxia Relies Upon Measurements To Which Dr. Vilke Could Not Possibly 

Have Had Access From Body Camera Footage.

The scientific opinions set forth in Dr. Vilke’s expert report cannot be based on witness 

testimony, because the same would necessitate credibility determinations that are within the sole 

purview of the finder of fact.

1 Therefore, Dr. Vilke’s opinion that the officers did not contribute 

to Mr. Muhaymin’s death by positional asphyxiation must be grounded in his own observations 

of the body camera footage. However, by Dr. Vilke’s own description, this is simply not possible.

When asked “what would need to happen physiologically for a person who is being restrained by 

the police for them to suffer from asphyxiation,” Dr. Vilke responded as follows:

A. They'd have to be put into a position in which they are unable to ventilate. 

[...] that could be putting enough weight [...] onto a position that restricts 

ventilations significantly enough, meaning blocking the ability to move air 

in and out, for a long enough period of time that physiologically you would 

retain carbon dioxide, drop your oxygen level, and then go into cardiac arrest. 

You'd have to look -- you know, it's going to be based on weight, position, 

timing, and what's going on with the individual during that episode.

1

It is standard judicial practice in both federal and state courts throughout the United States to 

exclude expert opinion that is intertwined inextricably with, and rests on, improper credibility 

determinations. See e.g., United States v. Scop, 846 F.2d 135, 142 (2d Cir. 1988); Parrish v. State,

139 Ala. 16, 36 So. 1012 (1904); Harvey v. State, 207 So. 2d 108, 118 (Miss. 1968); Brouillette 

v. Weymouth Shoe Co., 157 Me. 143, 145 (Me. 1961).
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October Deposition, pp. 24:18-25:9 (emphasis added). When asked specifically about how long 

it would take for someone to asphyxiate, Dr. Vilke explained:

A. So if you're having – if you're having complete ventilation blockages, 

meaning there is no air moving whatsoever, which is not the case here, then 

it's about five minutes, most people will sort of quote as a time period to 

cause asphyxiation. If there is movement of air in and out, then it takes much 

longer because you are still ventilating. So that's the marker of time there.

Q. (Continued by MR. CHAMI:) So it depends on how much area is moving 

in and out, right?

A. How much air movement is moving in and out or the restrictions on that. 

Yes.

November Deposition, pp. 64:18-65:4 (emphasis added).

To summarize, in order for Dr. Vilke to determine whether asphyxiation was the cause of 

Mr. Muhaymin’s death, he would need to know (1) the weight being placed on Mr. Muhaymin’s 

back, (2) the position of the weight (i.e., where on Mr. Muhaymin’s back the force was applied),

(3) exactly how long the weight was placed on Mr. Muhaymin’s back, and (4) how much air Mr. 

Muhaymin was able to inhale and exhale throughout the entire ordeal. 

Ms. Muhaymin and her counsel respectfully request that the Court watch the body camera 

footage and attempt to acquire the information that Dr. Vilke himself states is necessary to 

determine whether asphyxiation was the cause of death. There is no possible way to watch the 

body camera footage and determine with any level of accuracy the amount of weight being 

placed, where exactly that weight was placed at all times during the encounter, how long the 

weight was placed, or how much the weight impacted Mr. Muhaymin’s ability to inhale or exhale. 

Beyond the simple fact that most of these variables require measurement equipment to determine, 

even as to the one variable that might be ascertainable without equipment, length of time, the 
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constant and erratic movement in the video make it incredibly difficult to tell how long the weight 

was applied.

Either (1) Dr. Vilke is making credibility determinations and relying upon the testimony 

of Defendant Officers in making the necessary measurements (a completely inappropriate basis 

for an expert report), or (2) he is simply guessing the information necessary to form his “expert” 

opinion. As this Court noted last year, “an opinion that is an insightful, or even inspired, hunch 

is not admissible if it lacks scientific rigor.” Davis v. McKesson Corp., No. CV-18-1157-PHXDGC, 2019 WL 3532179, at *7 (D. Ariz. Aug. 2, 2019).

In the current situation, where Dr. Vilke will be telling an impressionable jury, with 

limited medical background, that he knows to a medical certainty that Mr. Muhaymin did not die 

of positional asphyxiation, reliance on either (1) determinations of Defendant Officers’ 

testimony, or (2) a guess is not permissible. Gen. Elec. Co., 522 U.S. at 146 (“A court may 

conclude that there is simply too great an analytical gap between the data and the opinion 

proffered.”); Daubert II, 43 F.3d at 1321 (“federal judges must exclude proffered scientific 

evidence under Fed. R. Evid. 702 unless they are convinced that it [...] will not mislead the 

jury.”).

B. THE REPORT FAILS TO IDENTIFY SUFFICIENT BASES FOR DR. 

VILKE’S CONCLUSIONS

After a review of the facts in a light most favorable to the Defendants, Dr. Vilke opines 

that police conduct did not cause or contribute to the death of Mr. Muhaymin. Report, pp. 11-14. 

Dr. Vilke states that “the weight of the officers holding Mr. Muhaymin’s legs, lower back, arms, 

head, neck and hair would not have had any impact on breathing or the ability for Mr. Muhaymin 
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to ventilate effectively” and ultimately concludes that “there is no evidence that position, restraint 

or body weight caused or contributed to Mr. Muhaymin’s cardiac arrest and death.” Id., at p. 14.

These broad statements present multiple inexplicable assumptions. Dr. Vilke’s report 

never identifies the exact amount of weight he is assuming is on Mr. Muhaymin’s back. He never 

provides the estimated time that he is assuming passed during which pressure was placed upon 

Mr. Muhaymin, nor an estimation of the location of the pressure throughout the incident. Dr. 

Vilke expressly admits that “other factors like agitation, struggle, or underlying medical 

conditions may result in respiratory compromise” (November Deposition, pg. 97:6-12) and that 

a determination of asphyxiation depends upon “what's going on with the individual during [the] 

episode” (October Deposition, p. 25:8-9), yet his Report completely fails to explore the 

possibility that such factors may have been involved. The incident wherein officers focused their 

body weight onto Mr. Muhaymin’s back for a prolonged period of time occurred without any 

sort of vitals monitoring or weight measurements. Despite this fact, Dr. Vilke simply concludes, 

solely from watching body camera footage (or by making inappropriate credibility 

determinations of the Defendant Officers’ testimony), that the officers did not contribute to Mr. 

Muhaymin’s death. This is a medical conclusion for which no support is offered.

An expert’s report must provide the method, facts and experience relied upon in reaching 

a conclusion. Daubert I, 509 U.S. at 592-593. As the United States Supreme Court made clear, 

“conclusions and methodology are not entirely distinct from one another” and nothing “requires 

a district court to admit opinion evidence that is connected to existing data only by the ipse dixit

of the expert.” Gen. Elec. Co., 522 U.S. at 146. “A court may conclude that there is simply too 

great an analytical gap between the data and the opinion proffered.” Id. Dr. Vilke’s report and 
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opinion constitute exactly what these principles aspire to sequester from a jury’s consideration: 

“Expert” conclusions which are not clearly and scientifically connected to the facts of the case.

Due to the large analytical gap between the lack of actual data gathered by Dr. Vilke in his 

extremely broad determination that there is no possibility that the officer’s weight contributed to 

Mr. Muhaymin’s asphyxiation, the court should exclude Dr. Vilke’s testimony and Report. Id.

C. DR. VILKE’S RESEARCH IS BOTH UNRELIABLE AND INAPPLICABLE 

TO THIS CASE

The Federal Rule of Evidence 702 imposes upon the Court an obligation to ensure that 

scientific testimony is both relevant and reliable. Kumho Tire Co. v. Carmichael, 526 U.S. 137, 

147, 119 S. Ct. 1167, 1174, 143 L. Ed. 2d 238 (1999) (citing Daubert I, 509 U.S. at 589) In 

supporting his broad conclusions that (1) Mr. Muhaymin did not die of asphyxiation, and that (2) 

the officers did not contribute to Mr. Muhaymin’s death, Dr. Vilke cites to a number of studies, 

both practical and epidemiological, approximately 65% of which were published by Dr. Vilke

himself. November Deposition, pp. 33:10-34:16. These studies are both irrelevant to this case 

due to their inherently dissimilar fact patterns, and unreliable due to the obvious conflict of 

interest that exists when a scientist conducts “science” for the sole purpose of testifying for a 

specific side in civil litigation.

1. Dr. Vilke’s Research Is Irrelevant To This Case.

Exactly zero of Dr. Vilke’s studies include examinations of fact patterns that are in any 

way similar to the manner of Mr. Muhaymin’s death. None of the studies involved the placement 

of weights onto the backs of test subjects in amounts heavier than two hundred and twenty-five 

pounds. November Deposition, p. 28:10-13. The test subjects in all of the studies involving 
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weights heavier than twenty-five pounds were explicitly screened for any recreational drug use 

(Id., at p. 30:8-13) and subjects in studies involving weights heavier than fifty pounds were 

generally screened for serious underlying health concerns (Id., at p. 29:6-30:3).

2 Furthermore, 

none of the studies were designed to emulate the stress and fear naturally existing when a human 

is being arrested, restrained and tied up by his arms and legs with a “hobble,” and sat upon by 

half a dozen armed individuals. Id., at pg. 94:13-15.

In sum, in reaching his conclusion that there was not enough weight on Mr. Muhaymin’s 

back to cause asphyxiation, Dr. Vilke relies exclusively on studies which measured the ability to 

inhale and exhale in relatively healthy, drug-free individuals who were laying safely in a 

controlled environment with no stressors added (other than previous exercise) and bearing weight 

no greater than two hundred and twenty-five pounds. It is difficult to imagine a set of facts more 

dissimilar to the incident which resulted in Mr. Muhaymin’s death. 

“[S]omething doesn't become ‘scientific knowledge’ just because it's uttered by a scientist; 

nor can an expert's self-serving assertion that his conclusions were ‘derived by the scientific

method’ be deemed conclusive...” Daubert II, 43 F.3d at 1315–16. “[The Court’s] task, then, is 

to analyze not what the experts say, but what basis they have for saying it.” Id. at 1316. “[T]he 

party presenting the expert must show that the expert's findings are based on sound science...” 

Id. As the gatekeeper, the Court reviews an expert’s opinion testimony for “overall sufficiency 

2 Dr. Vilke references only one study, involving weights from twenty-five to fifty pounds, wherein 

participants were not screened for underlying health concerns.
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of the underlying facts and data, and the reliability of the methods, as well as the fit of the methods 

to the facts of the case.” W.R. Grace, 504 F.3d at 762.

It is not possible for Defendants to show that Dr. Vilke’s conclusions are based on “sound 

science” or that the underlying research methodology “fits” in this case. The most that Dr. Vilke

could testify to is that healthy, drug-free individuals do not usually asphyxiate under weights 

lighter than two hundred and twenty-six pounds when lying in controlled, stress-free 

environments. However, this is not the case before the Court, nor the case to be put to the jury.

Mr. Muhaymin was homeless, suffered from mental illness and drug addiction, was under the 

influence of methamphetamine, and in the process of being physically manhandled by multiple 

armed police officers. How the officers’ actions, specifically the applying of weight to Mr. 

Muhaymin’s back, affected his ability to breath in conjunction with other compounding factors 

is simply not answered by any of the research conducted by Dr. Vilke. There is, yet again, a 

massive “analytical gap” between the conclusions reached by Dr. Vilke and the information 

available to him. Gen. Elec. Co., 522 U.S. at 146.

The Court should not permit Dr. Vilke to opine to a medically unsophisticated jury that it 

is not possible for the officer’s actions to have caused Mr. Muhaymin’s death based solely upon 

scientific studies that could not be more dissimilar to the facts of this case. Doing so carries the 

significant danger that the jury will be misled by Dr. Vilke’s “expert” representations, when the 

same are based on nothing more that wholly irrelevant scientific studies. Daubert II, 43 F.3d at 

1321.
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2. Dr. Vilke’s Research Is Unreliable.

“Federal Rule of Evidence 702 imposes a special obligation upon a trial judge to ‘ensure 

that any and all scientific testimony ... is not only relevant, but reliable.’” Kumho Tire Co., 526 

U.S. at 147 (quoting Daubert I, 509 U.S. at 589). In considering the reliability of an expert’s 

testimony, a “‘very significant fact’” is whether the expert has ‘developed [his] opinions 

expressly for purposes of testifying,’ since ‘a scientist's normal workplace is the lab or the field, 

not the courtroom or the lawyer's office.’” Lust By & Through Lust, 89 F.3d at 597 (quoting 

Daubert II, 43 F.3d at 1317).

For the past two decades, Dr. Vilke has regularly, and almost exclusively, testified on 

behalf of defendants in civil cases where wrongful death by asphyxia was alleged against police 

officers. October Deposition, pp. 21:21-25; 22:11-17. Dr. Vilke’s research and publications 

regarding positional asphyxia began, not-so-coincidently, roughly when Dr. Vilke began 

testifying as an expert, and continued on while municipalities and police forces continued to 

retain his services. November Deposition, pp. 80:8-82:15. Despite Dr. Vilke’s protestations that 

he has testified for plaintiffs before, he admits that only one such case involved asphyxia, and 

that case occurred so long ago that he no longer recalls the name. October Deposition, p. 22:6-

17. 

Dr. Vilke’s research began with, and has continued alongside, his two-decade career of 

testifying for police departments and municipalities in wrongful death lawsuits. All of his studies 

in the area were conducted during this time period, where every incentive weighed in the 

direction of determining that positional asphyxiation is not generally possible during police 

encounters. As this Court has noted, “the most persuasive reason for concluding that an expert's 
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testimony is derived from scientific method is that ‘the testimony . . . is based directly on 

legitimate, preexisting research unrelated to the litigation.” U.S. v. Crumby, 895 F. Supp. 

1354, 1361 (D. Ariz. 1995) (quoting Daubert II, 43 F.3d at 1317) (emphasis added) (internal 

quotation marks omitted). It cannot reasonably be contended that the research relied upon by Dr. 

Vilke’s testimony and Report was unrelated to this litigation. It was undertaken precisely because 

Dr. Vilke was being retained as an expert in wrongful death cases for police and municipalities 

such as Ms. Muhaymin’s instant case. It is therefore not reliable scientific evidence and should 

be excluded. Kumho Tire Co., 526 U.S. at 147.

D. DR. VILKE IS NOT QUALIFIED TO REBUT PLAINTIFF’S EXPERT 

WITNESS

In his Rebuttal Report, Dr. Vilke lays out his disagreement with Plaintiff’s expert witness, 

Dr. Bennet Omalu, regarding the cause of Mr. Muhaymin’s death. As Plaintiff has already 

explained why Dr. Vilke is utterly unqualified, both in general and specifically in this case, to 

make cause of death determinations, Plaintiff will not belabor the point. However, a couple of 

points are worth noting. First, unlike Dr. Vilke, Dr. Omalu is a pathologist whose regular practice 

includes autopsy and anatomic pathology, clinical pathology and toxicology, forensic pathology,

and neuropathology. Dr. Vilke is an emergency room physician. He is facially unqualified to 

“rebut” a pathologist’s opinion regarding cause of death. 

Second, unlike Dr. Vilke’s report, Dr. Omalu’s expert opinion is based upon his own 

examination and testing of actual lung, heart, and brain tissue samples taken from Mr. 

Muhaymin’s body. His ultimate conclusions are founded, in part, upon the levels of oxygen and 

carbon dioxide present in those tissue samples. Because he engaged in no actual review of Mr. 
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Muhaymin’s body, Dr. Vilke does not possess information sufficient to rebut Dr. Omalu’s 

findings.

Dr. Vilke is simply not qualified, in general or specifically to this case, to rebut Dr. 

Omalu’s methods or findings. The Court should preclude Dr. Vilke from testifying in rebuttal to

Dr. Omalu’s expert report.

IV. CONCLUSION

Dr. Vilke’s Report, Rebuttal Report, and anticipated testimony are comprised of a 

collection of unsupported conclusions and opinions in violation of Fed. R. Civ. P. 26, Fed. R. 

Evid. 702, and Daubert. Dr. Vilke’s baseless opinions are not accompanied or supported by 

reliable experience or scientific methods and procedures. Dr. Vilke has no qualifications to make 

cause of death determinations, being neither a trained pathologist nor a medical examiner, and 

he failed to actually examine Mr. Muhaymin’s body, regardless. Further, the analytical gap 

between Dr. Vilke’s conclusions and the factors implicated in an asphyxiation case is 

insurmountable, and all of Dr. Vilke’s opinions are based on irrelevant and unreliable studies 

performed by Dr. Vilke in anticipation of testifying for defendants in wrongful death cases. Dr. 

Vilke’s opinions are therefore an assortment of “mere subjective beliefs of unsupported 

speculation.” Claar v. Burlington Northern R. Co., 29 F.3d 499, 501 (9th Cir. 1994). The obvious 

deviation from the long-held requirements of Fed. R. Civ. P. 26, Fed. R. Evid. 702, and Daubert

warrant the preclusion at trial of Dr. Vilke, his Report, his Rebuttal Report, and any of his 

opinions.
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Date: April 2, 2021 PRICE LAW GROUP, APC

By: /s/ David A. Chami 

David A. Chami, AZ #027585

david@pricelawgroup.com

Attorneys for Plaintiff
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CERTIFICATE OF SERVICE

I hereby certify that on April 2, 2021, I electronically filed the foregoing with the Clerk of 

the Court using the ECF system, which will send notice of such filing to all attorneys of record in 

this matter. Since none of the attorneys of record are non-ECF participants, hard copies of the 

foregoing have not been provided via personal delivery or by postal mail.

/s/ Florence Lirato