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IN THE UNITED STATES DISTRICT COURT

FOR THE NORTHERN DISTRICT OF ILLINOIS

WESTERN DIVISION

TYLER TREXLER,

 Plaintiff, 

 v. 

CITY OF BELVIDERE, et al,

 Defendants.

 Case No. 3:20-cv-50113

 Honorable Iain D. Johnston

 

MEMORANDUM OPINION AND ORDER

The situation of the competing motions before the Court is odd. Initially, as is 

well known by civil rights counsel (and counsel on both sides of this case are 

experienced civil rights attorneys), the Court disfavors use of force “experts.” The 

Court routinely bars these proffered opinion witnesses. See Agnew v. Cater, 18-cv50035, 2022 U.S. Dist. LEXIS 31604, at *17 n. 12 (N.D. Ill. Feb. 23, 2022). Even the 

Magistrate Judges warn counsel not to waste their time and money on these types 

of “experts.” But here we are. Moreover, the reasoning for this Court’s repeated 

barring of use of force “experts” is borne out in the parties’ own briefing in this case. 

Each side marshals the same arguments against the competing “expert,” while 

simultaneously ignoring those arguments when confronted with the opponent’s 

motion to bar.

This exercise is not a good use of anybody’s time and resources. And it 

certainly does not further the goals of Rule 1. FED. R. CIV. P. 1.

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If civil rights counsel—both plaintiff and defendant—have not yet 

comprehended the point, the Court will be clear. Use of force “experts” find no 

quarter at the Stanley J. Roszkowski United States Courthouse, particularly when 

they play judge and offer legal conclusions. Retired law enforcement officers and 

academics should pedal their wares elsewhere. 

* * *

After being kicked, beaten, and bitten by a police canine, Plaintiff Tyler 

Trexler sued defendants City of Belvidere (City) and officer Brandon Parker 

alleging they violated his constitutional rights. Before the Court is Plaintiff’s motion 

to bar the entire testimony of Defendants’ opinion witness, Dr. Charles Mesloh. Dkt. 

93. Similarly, Defendants also filed a motion to bar the entire testimony of 

Plaintiff’s opinion witness, Ernest Burwell. Dkt. 96. Each side responded to the 

other party’s motion. Dkt. 100, Dkt. 102. For the following reasons, Plaintiff’s 

motion is granted, and Defendants’ motion is granted in part and denied in part.

I. BACKGROUND

On August 9, 2018, at 12:48 a.m., Plaintiff and a female companion were 

walking on the sidewalk of a street in Belvidere, Illinois. Defendant Parker was on 

patrol that morning and drove past Plaintiff. According to Parker, he believed 

Plaintiff and his companion were underage and out in violation of the local curfew.

So, Defendant Parker made a U-turn, drove up on the sidewalk, and parked his 

vehicle in front of Plaintiff and his companion.1 Defendant Parker exited his vehicle 

1 These facts are taken from the dash-camera video of Defendant Parker’s patrol car, Dkt. 93-3. No 

body camera footage is available because, apparently, Belvidere police officers were not equipped 

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with his canine, a German Sheppard named Monti, and approached Plaintiff. 

Within eight seconds of Defendant Parker exiting his vehicle, he kicked Plaintiff 

causing him to fall into the street, outside the frame of the vehicle’s dash-camera, 

where Defendant Parker quickly followed. What happens next is captured only 

through the dash-camera’s audio. Defendant Parker is heard screaming a command 

to Monti, ordering Plaintiff not to move, while Plaintiff is heard screaming “I’m 

down” and “I’m not moving.” During this altercation, Plaintiff was bitten by Monti

and handcuffed. Plaintiff later pled guilty to aggravated resisting or obstructing a 

peace officer. 

As a result of the August 9, 2018, incident with Officer Parker, Plaintiff filed

an action. The action contained two claims against Officer Parker under 42 U.S.C. § 

1983 alleging that his Fourth Amendment rights were violated. In Count I, Plaintiff 

alleges that he was subjected to an unreasonable seizure, and in Count II he alleges 

that Officer Parker used excessive force during the encounter. In Count III, Plaintiff 

brings a Monell claim against the City of Belvidere, alleging that the City had 

policies, practices, and customs of failing to investigate and discipline officers for 

misconduct, failing to adequately train and supervise officers, filing false charges, 

and maintaining a “code of silence” about officer misconduct. In Count IV, Plaintiff

with body cameras. That’s unfortunate. The Court has lamented the absence of body camera video

in the past. Agnew, 2022 U.S. Dist. LEXIS 31604, at 2 n.1; Pennie v. City of Rockford, 19-cv-50120, 

2022 U.S. Dist. LEXIS 19632, at *1–2 (N.D. Ill. Feb. 3, 2022). On the flip side, the Court has 

commented on the usefulness of body camera video to resolve disputes. For example, the City of 

Freeport’s body cameras allowed this Court to resolve very contentious litigation short of trial. 

Dukes v. Freeport Health Network Mem. Hosp., 19-cv-50189, 2022 U.S. Dist. LEXIS 61453, at 2 n.1 

(N.D. Ill. Apr. 11, 2022). New Illinois legislation requires body cameras, so, hopefully, the absence of 

video will no longer be an issue. 

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asserts an indemnification claim under 745 ILCS 10/9-102 against the City of

Belvidere, seeking to hold it liable for any judgments arising from Officer Parker’s 

actions. 

II. LEGAL STANDARD

The admissibility of opinion witness testimony is governed by Federal Rule of 

Evidence 702 and the principles established in the Supreme Court’s ruling in 

Daubert v. Merrell Dow Pharma., Inc., 509 U.S. 579 (1993). For a court to consider 

an opinion, the district court must evaluate four factors: (1) if the witness is 

qualified to provide the opinion; (2) whether the testimony will assist the trier of 

fact; (3) whether the testimony is based on sufficient facts or data and reliable 

principles and methods; and (4) whether the opinion is based on a reliable 

application of the principles and methods to the facts of the case. See Lees v. 

Carthage College, 714 F.3d 516, 521–22 (7th Cir. 2013); Daubert, 509 U.S. at 589–

96. Opinion testimony is not limited to scientific evidence. Kumho Tire Co., Ltd. v. 

Carmichael, 526 U.S. 137, 141, 147–49 (1999). The testimony can be based on 

personal experience and knowledge, so long as it is reliable. Id. at 150. “[E]xtensive 

hands-on experience over a meaningful period of time which a person develops a 

working expertise in a certain area” may qualify a person to provide opinion

testimony in that area. See Jones v. Lincoln Elec., Co., 188 F.3d 709, 725 (7th Cir. 

1999). The proponent bears the burden to establish the necessary evidentiary 

foundation for an opinion. Gopalratnam v. Hewlett-Packard Co., 877 F.3d 771, 782 

(7th Cir. 2017). 

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III. ANALYSIS 

Plaintiff’s motion seeks to bar the opinions of Defendants’ use-of-force expert 

Charles Mesloh. Dkt. 93. Plaintiff attacks Mesloh’s opinions, claiming that they are 

inadmissible legal conclusions or credibility determinations, and that his opinions

on the City’s use-of-force policies are irrelevant. Defendants argue that Mesloh’s 

opinions should not be barred because the opinions are offered as a rebuttal to 

Plaintiff’s expert opinions, and they should also be given an opportunity to present 

the same opinions that they later argue are inadmissible when offered by Plaintiff. 

As a general matter, the tactics of finger pointing, copycat arguments, or presenting 

“they did it first” arguments have no place in court. Because Defendants’ argument 

against barring Mesloh’s opinions relies on a “they did it first” theory, the Court will 

take up Defendants’ motion to bar Plaintiff’s expert opinion testimony first.

Defendants’ motion seeks to bar the opinions of Plaintiff’s use-of-force expert, 

Ernest Burwell. Dkt. 96. Defendants attack Burwell’s opinions on three fronts: (1)

Burwell is not qualified to be an expert on use-of-force or canine deployment 

standards in Illinois; (2) all of Burwell’s opinions are inadmissible legal conclusions

or improper credibility determinations; and (3) Burwell’s opinion on Officer Parker’s 

compliance with industry standards for use of force and canine policies is irrelevant.

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A. Plaintiff’s Use-of-Force Expert, Ernest Burwell

Defendants seek to bar the entirety of Burwell’s opinions. They claim that he is 

not qualified to offer any opinions on Illinois police practices, he relies on credibility 

determinations he is not entitled to make, he makes inadmissible legal conclusions, 

and offers irrelevant opinions on Defendants’ compliance with industry standards 

for use-of-force. The Court finds that most of Burwell’s testimony inadmissible, but 

a sliver is admissible. Therefore, Defendants’ motion is granted in part and denied 

in part. 

a. Burwell is Qualified to Offer Opinions on Police and Canine Practices.

Defendants argue that Burwell is not qualified to give opinion testimony for two 

reasons. First, he has no knowledge of the applicable law enforcement standards

that apply in Illinois. Mot. to Bar Burwell, Dkt. 96 at 3. Second, Defendants argue 

that any specialized knowledge Burwell may have is “woefully out of date.” Id. 

For a court to consider an opinion, the witness must be qualified to provide that 

opinion. Daubert, 509 U.S. at 588; FED. R. EVID. 702. Defendants’ argument that 

Burwell is not qualified to give an opinion on police practices, despite his thirty 

years of experience as a police officer, canine training officer, and canine handler, is

perplexing and meritless. Just up Interstate 90, Judge Conley bluntly—and 

correctly—rejected this argument. See Rivera v. Heck, No. 16-CV-673-WMC, 2018

U.S. Dist. LEXIS 1555294, at *6 (W.D. Wis. Sep. 12, 2018) (“[T]he assertion that 

Ernest Burwell’s some 30 years’ experience as a Los Angeles Deputy Sheriff, SWAT 

team member and trainer does not qualify him as an expert in police practices is 

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laughable.”) Defendants also argue that Burwell is not qualified because his 

knowledge on police practices is limited to the standards of California, not Illinois.

Defendants point to U.S. v. Brown in support of their argument. But the holding of 

that case undermines their argument. In Brown, the 7th Circuit stated that the 

“excessive-force inquiry is governed by constitutional principles, not policedepartment regulations ... which are not nationally uniform, nor are they static.” 

871 F.3d 532, 537–38 (7th Cir. 2017) (the task is to “determine how a reasonable 

officer would act in the circumstances, not how an officer in a particular local police 

department would act.”) Therefore, it is inconsequential that Mr. Burwell’s opinions 

are based, at least in part, on his thirty years of experience in California.

(Consistent with the inconsistency of positions, Defendants’ own opinion witness is 

not from Illinois, either.)

Further, Daubert and its progeny do not require a proffered expert witness to 

currently or previously work in the precise location of the dispute, the only 

requirement is that the witness have specialized knowledge of the subject matter. 

FED. R. EVID. 702; Kumho Tire Co., 526 U.S. at 141; Loeffel Stell Prods. v. Delta 

Brands, 372 F. Supp. 2d 1104, 1113 (N.D. Ill. 2005) (“A lack of specialization 

generally does not affect the admissibility of the opinion, only its weight.”) Burwell

has a plethora of qualifications in police and canine practices; he has almost thirty

years’ experience as a Deputy Sherriff, received multiple specialized trainings on

canine handling, conducted thousands of assignments with a canine, trained and 

evaluated canines, trained hundreds of officers across the nation on best practices 

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for police service canines, and received trainings on use-of-force policies. Taken 

together, these trainings and experiences qualify Burwell to present opinion

testimony, provided the testimony is otherwise admissible (which it generally isn’t.)

Kumho Tire Co., 526 U.S. at 142 (“[A] district court [has] the same broad latitude 

when it decides how to determine reliability as it enjoys in respect to its ultimate 

reliability determination.”)

Defendants also argue that even if Burwell has specialized knowledge, any 

knowledge is “woefully out of date.” Mot. to Bar Burwell, Dkt. 96, at 3. It is true 

that Burwell is years removed from both working as a police officer and receiving 

his last formal training on police canine practices. But unlike the legal profession, 

there are no continuing education requirement for an expert opinion witness; 

instead, Defendants stale knowledge argument goes to the weight of Burwell’s 

opinions, not its admissibility. Estate of Robinson ex rel. Irwin v. City of Madison, 

No. 15-CV-502-JDP, 2017 U.S. Dist. LEXIS 20733, at *29 (W.D. Wis. Feb. 13, 2017).

b. Burwell’s opinions on the reasonableness of Officer Parker’s use-offorce are inadmissible. 

Defendants argue that Burwell’s opinion that Defendant Parker’s actions were 

both unreasonable and an excessive use of force is improper and should not be 

admitted. Federal Rule of Evidence 704 allows opinion witnesses to testify as to the 

ultimate issue in an action. But Rule 704 still does not authorize opinions to be 

legal conclusions. Good Shepherd Manor Found., Inc. v. City Momence, 323 F.3d 

557, 564 (7th Cir. 2003). Sometimes, there is a thin line between an “ultimate issue” 

and a legal conclusion. Id; Burkhart v. Washington Metro. Area Transit Auth., 112 

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F.3d 1207, 1212 (D.C. Cir. 1997). But here, the line is clear. The following examples 

show that many of Burwell’s opinions are unadorned legal opinions. “Parker’s acts 

were wanton towards Trexler, and in disregard to Trexler’s safety and his 

constitutional rights.” Mot. to Bar Burwell, Dkt. 96-1 at 15. “Parker’s kick to 

Trexler was also an inappropriate use of force.” Id. at 16. “The canine attack on 

Trexler was completely unjustified. It was unreasonable and excessive force.” Id. at 

19. The Seventh Circuit has on many occasions reiterated that an expert may not 

offer legal opinions. Jimenez v. City of Chi., 732 F.3d 710, 720 (7th Cir. 2013); 

Thompson v. City of Chi., 472 F.3d 444, 458 (7th Cir. 2006) (barring witnesses who 

were proffered to testify that defendant “used excessive force”). Burwell’s opinions 

about what was “proper”, “unjustified”, “unreasonable”, or “excessive” regarding the 

arrest of Plaintiff, are all legal conclusions and must be barred. There is one expert 

in the courtroom for legal opinions—that’s the judge. Jimenez, 472 F.3d at 720. 

Defendants also argue that Burwell should be barred from referencing or 

applying the standards set forth in Graham v. Connor because any opinion or 

application of the standards are legal conclusions on a determinative issue. 

Defendants are correct, applications of law to fact are matters left to the judge and 

jury and are inadmissible opinions by an expert. Shepard Manor Found., Inc., 323 

F.3d at 564 (noting that “expert testimony as to legal conclusions that will 

determine the outcome of the case is inadmissible.”); Christiansen v. City of Tulsa, 

332 F.3d 1270, 1283 (10th Cir. 2003) (experts may not state legal conclusions drawn

by applying the law to the facts); Anderson v. City of Chi., 454 F. Supp.3d 808, 819 

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(N.D. Ill. 2009) (excluding expert testimony that “amounts to an instruction on the 

law and application of the law to the facts.”)

Legal conclusions are also inadmissible because they are not helpful to the jury. 

Thompson, 472 F.3d at 458. Here, jurors can simply watch the dash-camera video, 

apply their own understanding of reasonableness and determine if it was 

reasonable for Defendant Parker to kick and allow Monti to bite Plaintiff, all within 

a mere eight seconds of Parker exiting his patrol car. See Brown ̧ 871 F.3d at 537.

An expert opinion on this would be both unhelpful and unnecessary. 

c. Burwell’s opinions about Defendant Parker’s use-of-force in other cases

is admissible.

Plaintiff brings a Monell claim against the City alleging it had policies, practices, 

and customs of failing to investigate and discipline officers for misconduct, failing to 

adequately train and supervise officers, filing false charges, and maintaining a 

“code of silence” about officer misconduct. Plaintiff proffers Burwell’s opinions on 

Parker’s use of force in other instances in support of this Monell claim. Defendants

argue that Burwell’s opinions on Officer Parker’s prior conduct are inadmissible 

because they are legal conclusions and must be barred under Federal Rule of 

Evidence 404(b) as prior bad acts.

There are three ways to hold the City liable under Monell. In this case, Plaintiff 

attempts to establish liability through a theory that there was “a wide-spread 

practice that although not authorized by written law and express policy, is so 

permanent and well-settled as to constitute a custom or usage with the force of 

law . . .” Johnson v. Cook Cty., 526 Fed. Appx. 692, 695 (7th Cir. 2013). An 

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unconstitutional policy can include both implicit policies as well as a gap in express 

policies. Dixon v. Cook Cty., 819 F.3d 343, 348 (7th Cir. 2016). But a plaintiff 

cannot solely rely on his own case or even “a handful of others,” for a Monell claim. 

Daniel v. Cook Cnty., 833 F.3d 728, 742 (7th Cir. 2016). To establish a pattern there 

must, of course, be other instances of similar behavior that a plaintiff alleges. Gill v. 

City of Milwaukee, 850 F.3d 335, 344 (7th Cir. 2017). 

An analysis of previous instances of force by Officer Parker may assist the jury 

to determine if the City should be held liable under a Monell claim based on a 

theory that there was a de facto policy so well settled to constitute a custom or 

practice. FED. R. EVID. 702. A starting point to that analysis can be evaluating how 

Officer Parker previously used his canine against other citizens. See Martinez v. 

Salazar, Civ. No. 14-534, 2016 U.S. Dist. LEXIS 17317, at *24 (D.N.M. Dec. 14, 

2016) (“Thus, while national and generally accepted police practices may be 

relevant to proving a claim resting on municipal or supervisory liability, these same 

standards are not relevant to whether an individual officer acted reasonably under 

certain circumstances.”). Burwell’s opinions on previous instances that Officer 

Parker deployed his canine are admissible to the extent that the opinions are 

limited to whether those instances deviated from sound professional standards. 

(“[E]ach of the following bite incidents fell far below the standards of care for using 

and deploying a police canine to bite a person ... officers had hands on the suspect 

when Parker commanded his dog to bite a suspect.” Mot. to Bar Burwell, Dkt. 96-1 

at 17); (Additional frames of videos from other incidents where Officer Parker is 

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using the police service canine to bite subjects where simple hands on control holds 

would suffice. Mot. to Bar Burwell, Dkt. 96-1 at 32.) These opinions, however, are 

not sufficient to state a Monell claim but may be helpful and relevant to the jury in 

deciding if the claims Plaintiff brings against the City have merit. Adams v. 

Ameritech Servs., Inc. ̧231 F.3d 414, 425 (7th Cir. 2000) (“No one piece of evidence 

has to prove every element of plaintiff’s case; it need only make the existence of ‘any 

fact that is of consequence’ more or less probable.”); Jimenez, 732 F.3d at 721–22 

(an expert may testify whether an officer’s acts departed from sound professional 

standards). 

Although Rule 404(b) generally prohibits the use of prior bad acts to prove 

character and that the person acted in accordance with that character on a 

particular occasion, prior bad acts are admissible to establish a pattern for a Monell 

claim. See Gill, 850 F.3d at 344; Lepianka v. Vill. of Franklin Park, No. 03-C-2991, 

2004 U.S. Dist. LEXIS 5013 at *3–4 (N.D. Ill. Mar. 25, 2004) (admitting evidence of 

defendant officer’s disciplinary records as helpful to establish a Monell claim); Fed. 

R. Evid. 404(b)(2); see also Ramirez v. County of L.A., 231 F.R.D. 407, 412 (C.D. Cal. 

2005). So, Burwell’s testimony on Officer Parker’s prior use of force behavior will be 

limited to Plaintiff’s Monell claim and may not be used as evidence towards any 

other claims. United States v. Gomez, 763 F.3d 845, 860 (7th Cir. 2014)

(“Appropriate jury instructions may help reduce the risk of unfair prejudice 

inherent in other-act evidence.”); DeLeon-Reyes v. Guevara, No. 18-CV-01028, 2020 

U.S. Dist. LEXIS 47333 at *21–22 (N.D. Ill. Mar. 18, 2020) (“[N]on-propensity 

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evidence under Rule 404(b) is admitted in a limited fashion due to Rule 403 

concerns.”). And if this type of evidence were barred by Rule 404(b), one would 

wonder how a plaintiff could ever prove a Monell claim based upon a custom or 

practice.

d. Burwell’s interpretation of the dash-camera video is inadmissible.

As noted above, under Rule 702 expert testimony is relevant only if it assists the 

jury in understanding the evidence or in determining a contested fact. FED. R. EVID.

702. Burwell’s report and deposition testimony contain numerous opinions 

regarding his observations and interpretations of Officer Parker’s dash-camera

video of the incident with Plaintiff. Burwell also states that his interpretation of the 

video is based in part on his common sense. Mot. to Bar Burwell, Dkt. 96-2, at 108. 

Opinion testimony based on common sense is unhelpful to a jury and is 

inadmissible. Beving v. Union Pac. R.R. Co., 447 F. Supp. 3d 786, 800 (S.D. Iowa

2019); In re Mirena IUD Prods. Liab. Litig., 169 F. Supp. 3d 396, 484 (S.D.N.Y. 

2016). Any expert testimony that interprets the video is both unhelpful and 

unnecessary because the jurors can simply watch the dash-camera video and 

interpret it for themselves. See Brown ̧ 871 F.3d at 537. “[E]xpert testimony does 

not help where the jury has no need for an opinion because the jury can easily reach 

reliable conclusions based on common sense, common experience, the jury’s own 

perceptions, or simple logic.” 29 Charles Alan Wright & Victor James Gold, Federal 

Practice and Procedure § 6265.2 (2d ed., April 2016 update). Therefore, any opinions 

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or testimony by Burwell regarding his interpretation of the dash-camera video are 

excluded. 

e. Burwell may rely on Plaintiff’s version of events, but the jury will 

determine the facts. 

Defendants argue that other portions of Burwell’s testimony should be excluded

because they plainly make factual findings that are central to Plaintiff’s claim, and 

thus usurps the jury’s function to weigh evidence and make credibility 

determinations. There is nothing inappropriate about Burwell’s reliance on an 

assumed set of facts provided by Plaintiff, so long as those facts are consistent with 

evidence that will be admitted. See Williams v. Illinois, 567 U.S. 50, 57 (2012) 

(noting that experts no longer must base an opinion on assumed facts to testify in 

the form of an answer to a hypothetical question) (“Under settled evidence law, an 

expert may express an opinion that is based on facts that the expert assumes, but 

does not know, to be true.”); Somerfield v. City of Chi., 254 F.R.D. 317, 320–21 (N.D. 

Ill. 2008). Plaintiff agrees that any of Burwell’s opinions that opine on Officer 

Parker’s credibility will not be offered as evidence for purposes of summary 

judgment or trial; and Plaintiff also stipulates that he will not offer any opinions for 

the purpose of making credibility determinations. Resp. in Opp. to Bar Burwell, 

Dkt. 102 at 22. Because Burwell appears to be basing his opinions on what he 

observed from the dash-camera video, and not which party’s version of events he 

believed to be accurate, Defendants argument that these opinions should be barred 

as “fact determinations” fails. Mot. to Bar Burwell, Dkt. 96 at 16; Garrit v. City of 

Chi., No. 16-CV-7319, 2022 U.S. Dist. LEXIS 6758, at * 9 (N.D. Ill. Jan. 13, 2022)

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(“[W]hen an expert’s opinion is based on his own credibility determinations, rather 

than factual assumptions, it must be excluded.”)

Nevertheless, as stated numerous times in this opinion, the jury can simply 

watch the dash-camera video themselves to determine the facts of the incident. So, 

these Burwell opinions will be excluded because they would not aid the jury. 

f. Some of Burwell’s testimony on police policies is admissible.

Next, Defendants seek to bar Burwell’s opinions regarding the City’s canine and 

use-of-force policies, and his opinion that Officer Parker did not comply with the 

policies. Defendants argue that the holding Thompson prohibits the introduction of 

evidence of violations of department general orders and national standards because

such evidence is irrelevant, immaterial, more prejudicial than probative, and 

inadmissible under Federal Rule of Evidence 401 and 403. Thompson, 472 F.3d at 

444. But, in Thompson, the court only kept out introduction of the actual text and 

provision numbers of the Chicago Police Department’s General Orders. Id. at 456. 

However, the holding in Thompson is distinguishable from this case because

Burwell makes opinions on potential breaches of department policies on canine use,

and Plaintiff is not offering the actual text of the policies or general orders for 

admission.

Further, the Seventh Circuit has cautioned that Thompson “should not be 

understood as establishing a rule that evidence of a police practice or procedure will

never be relevant” to an excessive force claim against a law enforcement officer. See 

Brown, 871 F.3d at 537. “Even though jurors can understand the concept of 

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reasonableness, in some cases they may not fully grasp particular techniques or 

equipment used by police officers in the field. In those instances, an expert’s 

specialized knowledge can ‘help the trier of fact to understand the evidence or to 

determine a fact in issue.’” Id. Although some jurors may own pet dogs, they almost 

certainly do not own trained police canines, so having expert testimony on the 

practices and circumstances when a reasonable police officer would deem it 

necessary to use a police canine in gaining control over a suspect might assist the 

jury. Florek v. Vill. of Mundelein, 649 F.3d 594, 602 (7th Cir. 2011) (noting expert 

testimony may help a jury determine whether it was reasonable police conduct to 

use specialized tools, such as a canine, to bring a suspect to heel). 

Plaintiff concedes that Burwell cannot opine that Officer Parker violated the 

City’s policies in this case and others. Resp. in Opp. to Bar Burwell, Dkt. 102 at 24. 

However, the Court finds that Burwell’s testimony on police canine policies might

be helpful to the jury in understanding when it is appropriate to use a canine.

g. Burwell’s opinion on Officer Parker’s state of mind is inadmissible. 

Defendants also move to exclude any opinion testimony regarding Officer 

Parker’s and Monti’s states of mind. Expert witnesses cannot opine on a person’s 

state of mind. See In re C.R. Bard, Inc., 948 F. Supp. 2d 589, 611 (S.D. W.Va. 2013); 

Quagliarello v. Dewees, 802 F. Supp. 2d 620, 626 (E.D. Pa. 2011). And if these 

witnesses cannot opine on a human’s state of mind, they certainly cannot opine on a 

canine’s state of mind. In support of these opinions by Burwell, Plaintiff fails to cite 

any authority and merely argues that “[t]his is exactly the type of expert opinion 

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Mr. Burwell is qualified to offer.” The Court is not persuaded by Plaintiff’s passing

argument. And because Plaintiff, as the proponent of the expert, bears the burden 

of demonstrating that the expert’s testimony is admissible under the Daubert

standard, and the rules of evidence, and has failed to do so, Burwell’s state of mind 

opinions are excluded. Gopalratnam, 877 F.3d at 782.

h. Burwell may not testify about topics that require medical expertise.

Burwell’s report includes descriptions of medical hazards and medical impacts of 

dog bites. Defendants move to bar Burwell from testifying on medical impacts 

associated with dog bites, claiming that he is unqualified to offer any medical 

opinions. Although Burwell does have extensive experience with police canines, this 

experience does not qualify him to render testimony on the medical impacts 

associated with dog bites. See Kumho Tire Co., 526 U.S. at 141. Even a wellqualified expert cannot simply parrot the opinions of experts in different fields. 

Dura Auto. Sys. of Indiana, Inc. v. CTS Corp., 285 F.3d 609, 614 (7th Cir. 2002); 

Agnew, 18-cv-50035, 2022 U.S. Dist. LEXIS 31604, at *21 (“The Seventh Circuit is 

hardly alone in not allowing the testifying expert to parrot the opinions of other 

experts upon whom they relied without sufficient evidence of the reliability of the 

underlying opinion.”) Courts routinely bar law enforcement practices opinion 

witnesses from giving medical opinions. See, e.g., Millward v. Bd. Of Cyt. Comm’rs 

of Teton, Case No. 17-CV-0117, 2018 U.S. Dist. LEXIS 231407, at *16 (D. Wy. Oct. 

19, 2018); Hernandez v. City of Albuquerque, 2003 U.S. Dist. LEXIS 26585, at *9–10 

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(D. N.M. Dec. 24, 2013). So, Burwell’s opinions related to medical impacts of dog 

bites are excluded. 

B. Defendants’ use-of-force expert, Charles Mesloh

Plaintiff seeks to bar Defendants’ use-of-force expert, Charles Mesloh, from 

testifying. Plaintiff claims that Mesloh’s testimony should be barred in its entirety 

because he relies on credibility determinations he is not entitled to make and makes 

inadmissible and incorrect legal conclusions. (Sound familiar?) In defense of 

Mesloh’s expert opinions, Defendants argue that the motion “must be denied” 

because his testimony “directly refutes and contradicts the opinions” of Plaintiff’s 

expert, Ernest Burwell. Mot. Opp. to Bar Mesloh, Dkt. 100 at 2. This argument is 

improper. Defendants are not entitled to present contradictory opinion testimony 

merely because it would be beneficial to their position, Mesloh’s opinions must 

independently satisfy the Daubert standards. The Court is also puzzled how

Defendants can in good faith proffer an expert witness that seeks to present expert

opinions in the same manner and topics that Defendants argued was improper in 

their 29 page motion against Plaintiff’s expert. See Mot. to Bar Burwell, Dkt. 96.

The argument essentially boils down to Defendants saying, “We know these 

opinions are inadmissible, but the opinions should be admissible because Plaintiffs 

did it first.” Two wrongs do not make a right. Mesloh’s testimony fails the Daubert 

standards and presents inadmissible legal conclusions and irrelevant opinions. 

Therefore, Plaintiff’s motion to bar Mesloh’s testimony is granted. 

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a. Mesloh cannot testify on the Reasonableness of Officer Parker’s 

Seizure.

Plaintiff argues that Mesloh should be barred from testifying on the 

reasonableness of Officer Parker’s seizure because it is not helpful to the jury and is 

an inadmissible legal conclusion. Defendants argue that these opinions are relevant 

and admissible by pointing the finger at Burwell’s testimony, again arguing that 

Burwell’s testimony is inadmissible. This argument does nothing to bolster 

Defendants’ position and is nevertheless irrelevant because Mesloh plainly makes

inadmissible legal conclusions and credibility determinations. For example, he 

opines, “Officer Parker’s belief that they were in violation of the curfew statute 

would make the stop acceptable . . .” Mot. to Bar Mesloh, Dkt. 93-1 at 7. Mesloh’s 

opinions do not help the jury establish a baseline, and instead invades the jury’s 

role and determines whether Officer Parker deviated from reasonable police 

practices. See Jimenez, 472 F.3d at 721. Therefore, Mesloh’s opinion on the 

reasonableness of the seizure is barred. 

b. Mesloh cannot testify on the reasonableness of Officer Parker’s use-offorce.

Defendants admit that Mesloh’s opinions were “designed to mirror and directly 

refute those offered by Plaintiff.” Mirroring the reasons stated in granting 

Defendants’ motion to exclude Burwell’s testimony on the reasonableness of Officer 

Parker’s use-of-force, Plaintiff’s motion to bar Mesloh’s opinions is also granted. See 

supra, Section A (b). The Court is compelled to point out that it is both a waste of 

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the Court’s resources and the client’s resources to retain experts that seek to opine 

on issues that the proffering party previously argued were inadmissible. 

Plaintiff also seeks to bar Mesloh from testifying as to the standards identified 

in Graham v. Connor because these are legal conclusions and are outcome 

determinative. Defendants respond by arguing that Plaintiff “completely ignores 

that his own expert’s report [sic] references this case and purports to apply this 

standard . . .” and “if Burwell’s references to Graham and the standards identified 

in that case are not barred, Dr. Mesloh’s testimony is properly admissible as 

rebuttal testimony.” Mot. Opp. to Bar Mesloh, Dkt. 100 at 10–11. Applying 

Defendants’ own logic, and for the reasons stated above, Mesloh’s application of the 

Graham standards is inadmissible and excluded. See supra, Section A (b); and see 

Shepard, 323 F.3d at 564.

c. Mesloh cannot testify on the City of Belvidere’s use-of-force policies.

Plaintiff also argues Mesloh’s opinions on the City’s written use-of-force policies

are irrelevant because Plaintiff’s claim against the City is not based on the 

adequacy of the official written policies. Instead, Plaintiff’s Monell claim against the 

City is premised on the contention that there is an unwritten de-facto policy of 

allowing excessive force with canines. One of the threshold hurdles for the 

admissibility of an expert opinion is that it assists the jury. Daubert, 509 U.S. at 

589–96; FED. R. EVID. 702. Because evidence on written policies that are not at issue 

in Plaintiff’s claim are not be helpful to the jury, Mesloh’s opinions on the City’s 

official policies are excluded. 

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IV. CONCLUSION

For these reasons, Defendants’ motion to bar Burwell’s testimony is granted 

in part and denied in part. Plaintiff’s motion to bar Mesloh’s testimony is granted in 

its entirety. 

Date: January 25, 2023

___________________________

Honorable Iain D. Johnston

United States District Judge

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