1 2 3 4 UNITED STATES DISTRICT COURT 5 NORTHERN DISTRICT OF CALIFORNIA 6 7 AARON MCLAUGHLIN, et al., Case No. 22-cv-07849-SVK

8 Plaintiffs,

ORDER RE MOTIONS TO

9 v. EXCLUDE EXPERT TESTIMONY

10 TESLA, INC., et al., Re: Dkt. Nos. 79, 81 11 Defendants.

12 Defendant Tesla, Inc. (“Tesla”) requests that the Court exclude the testimony of Plaintiffs’ 13 experts Drs. Anthony Andre and Timothy Fratto. See Dkts. 79, 81 (the “Motions”). The Parties 14 appeared for a hearing on the Motions on September 5, 2024. All necessary parties—Plaintiffs 15 and Tesla—have consented to the jurisdiction of a magistrate judge.1 See Dkts. 6-7. After 16 considering the Parties’ briefing, relevant law and the record in this action, and after hearing oral 17 argument, the Court GRANTS IN PART and DENIES IN PART the request to exclude Dr. 18 Andre’s testimony and DENIES the request to exclude Dr. Fratto’s testimony. The Court’s 19 reasoning is set forth below. 20 I. DR. ANDRE 21 Tesla seeks to limit the testimony of Dr. Andre, Plaintiffs’ human-factors expert, in two 22 respects.2 The first relates to the activation of autopilot mode in the vehicle on the day of the car 23

24 1 Plaintiffs also sued 100 Doe defendants. See Dkt. 1-2 ¶ 13. These Doe defendants are not 25 “parties” for purposes of assessing whether there is complete consent to magistrate-judge jurisdiction. See Williams v. King, 875 F.3d 500, 502-505 (9th Cir. 2017) (magistrate-judge 26 jurisdiction vests only after all named parties, whether served or unserved, consent); RingCentral, Inc. v. Nextiva, Inc., No. 19-cv-02626-NC, 2020 WL 978667, at *1 n.1 (N.D. Cal. Feb. 28, 27 2020) (Williams does not require consent of unnamed Doe defendants). 1 accident at the center of this lawsuit. Specifically, pursuant to Federal Rule of Evidence 702, 2 Tesla seeks to exclude any testimony from Dr. Andre that, on the day of the accident, Plaintiff 3 Aaron McLaughlin pulled on the car’s gear stalk twice or reasonably believed he had pulled on the 4 gear stalk twice. The second relates to Dr. Andre’s methodology. Specifically, pursuant to 5 Federal Rule of Evidence 703, Tesla seeks to exclude any testimony from Dr. Andre based upon 6 his review of internet posts allegedly reflecting reports of “mode confusion” by Tesla drivers. 7 Tesla also seeks to exclude the internet posts themselves. 8 A. Dr. Andre May Not Opine As To Whether Plaintiff McLaughlin Pulled The Gear Stalk Twice Or 9 Reasonably Believed He Did So On The Day Of The Accident 10 In the “Incident Summary” section of his expert report, Dr. Andre states that Plaintiff 11 McLaughlin “attempted to engage the Autopilot feature of his Tesla by pressing down twice on 12 the right-hand steering wheel stalk.” See Dkt. 86-1, Ex. 1 at 5. However, Dr. Andre does not 13 appear to include a similar statement in the “Summary and Conclusions” section of his report. See 14 id. at 32. Further, at the September 5 hearing, Plaintiffs did not clarify whether they intended to 15 offer this “opinion” at trial. Accordingly, the Court rules as set forth below. 16 At trial, Dr. Andre may restate any fact upon which he bases an opinion. Here, Plaintiff 17 McLaughlin testified that he does not remember whether he activated autopilot on the day of the 18 accident. See Dkt. 96-1 at 224:16-21, 225:19-24, 250:5-10, 252:4-12. He also testified that he 19 used the autopilot feature on “most days” and activated that feature by pulling twice on the car’s 20 gear stalk. See id. at 200:14-17, 202:4-9. On that record, Dr. Andre may testify, for example, that 21 Plaintiff McLaughlin testified that he engaged the autopilot feature most days and that that 22 testimony is the basis for a proffered opinion. What Dr. Andre may not do, however, is 23 extrapolate from Plaintiff McLaughlin’s testimony that, on the day of the accident: (1) Plaintiff 24 McLaughlin believed he had engaged autopilot; or (2) that that belief was reasonable. These 25 opinions would be unreliable and therefore inadmissible under Federal Rule of Evidence 702. To 26 the extent that Tesla seeks to exclude these two specific opinions only, the Court GRANTS that 27 1 request. 2 B. Dr. Andre May Opine Based Upon His Review Of Internet Posts 3 Tesla argues that the Court should exclude Dr. Andre’s opinions that he based upon his 4 review of internet posts because no expert would reasonably rely upon such anonymous, 5 unverified internet posts in support of an opinion. See Dkt. 79 at 6-7. Tesla also argues that the 6 Court should exclude the internet posts themselves because: (1) they constitute inadmissible 7 hearsay; and (2) their prejudicial effect substantially outweighs their probative value. See id. at 7- 8 9 (citing Fed. R. Evid. 703). Tesla further argued at the September 5 hearing that the Court should 9 exclude any reference in the internet posts to “mode confusion” as it relates to use of the autopilot 10 feature in a Tesla vehicle. Plaintiffs respond that human-factors experts like Dr. Andre routinely 11 rely on internet posts and suggest that any objection based on the internet posts’ prejudicial effect 12 is premature and more-properly reserved for a future motion in limine. See Dkt. 86 at 5. Plaintiffs 13 also suggested at the September 5 hearing that the internet posts constituted “notice” to Tesla, 14 thereby rendering them admissible under Federal Rule of Evidence 803. 15 With respect to the reasonability of relying on internet posts, Dr. Andre testified as 16 follows: 17 So, you know, my field is all about the user experience. And human factors 18 professionals learn from the science of our discipline and the actual experiences of 19 users with the products of interest. And so part of our methodology is to learn what users are saying or doing or complaining about as, um, one input to understanding 20 issues they may be having and perceptions they may be forming. So, um, it’s very common activity. I do it all the time. Teach it as a – as a technique. And so I did 21 my own analysis, and then I’m seeing if other actual users of the system in question have anything to say about these topics. And that’s what I’m presenting to the jury. 22

23 Dkt. 86-1, Ex. 2 at 162:12-25. Based on this testimony, the Court finds that Dr. Andre has 24 adequately validated his use of internet posts as a basis for opinions in his area of expertise. 25 Accordingly, the Court will permit Dr. Andre to express opinions based upon his review of 26 internet posts and DENIES Tesla’s request to exclude those opinions. 27 1 does not appear that the internet posts would be relevant if they did not concern the autopilot 2 feature in a Tesla vehicle. Thus, and in harmony with the ruling above that Dr. Andre may opine 3 based upon his review of internet posts, the Court will permit Dr. Andre to refer, in summary 4 fashion, to the content of the internet posts he reviewed and how his review informed his opinion. 5 Such a summary may include references to “mode confusion” as it relates to use of the autopilot 6 feature in Tesla vehicles if the internet posts support Dr. Andre’s opinion in that regard. As for 7 the admissibility of the internet posts themselves, the Court RESERVES that argument for the 8 forthcoming pretrial conference, at which time the issue may be addressed via motion in limine. 9 II. DR. FRATTO 10 The Court will address two of Tesla’s four grounds for exclusion of Dr. Fratto’s opinions 11 in this Order: (1) Dr. Fratto’s testimony is not helpful to the finder of fact because he cannot 12 opine that it is “more probable than not” that the car accident caused Plaintiff McLaughlin’s 13 injuries; and (2) Dr. Fratto’s testimony is unreliable because he fails to consider alternative 14 explanations for his conclusions.3 15 A. Dr. Fratto’s Testimony Will Help The Finder Of Fact 16 In Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579 (1993) (“Daubert I”), the 17 Supreme Court held that the Federal Rules of Evidence, and in particular Rule 702, require a 18 district court to ensure the reliability and relevance of an expert’s testimony. See id. at 597; see 19 also Kumho Tire Co. v. Carmichael, 526 U.S. 137, 147-49 (1999) (extending Daubert 20 requirements to assessments of all experts and not just scientific experts). Relevance, the basis for 21 the challenge at hand, concerns whether the expert’s opinion will assist the trier of fact. See 22 Daubert I, 509 U.S. at 591; see also Fed. R. Evid. 702(a). “In assessing whether the proffered 23 expert testimony ‘will assist the trier of fact’ . . .[, the Court] must look to the governing 24 25 3 The Court will address Tesla’s request to exclude Dr. Fratto’s testimony on the basis of Virginia 26 law concerning competency in a separate order. Tesla also requested that the Court exclude Dr. Fratto’s testimony concerning Plaintiff McLaughlin’s ability to return to work. The Court 27 understands that this opinion, if ever asserted, has been withdrawn, and the request to exclude that 1 substantive standard . . . .” Daubert v. Merrell Dow Pharms., Inc, 43 F.3d 1311, 1320 (9th Cir. 2 1995) (“Daubert II”). 3 In a tort case such as this one, where Dr. Fratto opines on causation, state law governs the 4 substantive standard. See, e.g., id. The laws of California and Virginia could possibly govern the 5 substantive issues in this action, and the laws of those two states do not conflict on the issue of 6 causation—both California and Virginia require a plaintiff to demonstrate that a subject incident 7 (here, a car accident) “more likely than not” caused their injury. Compare Ford Motor Co. v. 8 Boomer, 285 Va. 141, 159 (2013) (“The circuit court now needs to consider the experts’ opinions 9 as to whether the exposures by Ford and Bendix were each more likely than not sufficient to have 10 caused mesothelioma.”), with Daubert II, 43 F.3d at 1320 (“California tort law requires plaintiffs 11 to show not merely that Bendectin increased the likelihood of injury, but that it more likely than 12 not caused their injuries.” (citation omitted)), and Leslie G. v. Perry & Assocs., 43 Cal. App. 4th 13 472, 487 (2d Dist. Div 1 1996) (“A possible cause only becomes ‘probable’ when, in the absence 14 of other reasonable causal explanations, it becomes more likely than not that the injury was a 15 result of its action. This is the outer limit of inference upon which an issue may be submitted to 16 the jury.” (citation omitted)). 17 Tesla argues that Dr. Fratto’s reluctance to assign a percentage to the contributory effect of 18 Plaintiff McLaughlin’s pre-existing conditions on his post-accident cognitive impairment 19 demonstrates his inability to satisfy the “more likely than not” standard.4 See Dkt. 81-1 at 9-10. 20 Specifically, Tesla points to the following exchange from Dr. Fratto’s deposition: 21 Q. Okay. So you – it’s your opinion that his preexisting conditions may have 22 some – may be exacerbating some of – and be the cause of some of his cognitive 23 deficits. Is that fair?

24 A. I believe that they’re contributory, but I do not believe that they are the sole cause. 25 26

27 4 Plaintiffs do not appear to dispute the existence of Plaintiff McLaughlin’s pre-existing Q. Okay. But can you put a percentage on that? 1

2 A. I cannot put a percentage on that, no.

3 Q. What amount they contribute versus what amount the October 2020 accident contributes? 4 A. It’s difficult to put a percentage on that based on a neuropsychological 5 evaluation. 6 7 Dkt. 78-3 at 279:6-19. However, other testimony from Dr. Fratto’s deposition rebuts Tesla’s 8 position that an inability to assign a percentage to certain potential causes necessarily undermines 9 satisfaction of the “more likely than not” standard. Indeed, Dr. Fratto expressly explained how he 10 ruled out certain pre-existing conditions as causing some of Plaintiff McLaughlin’s cognitive 11 impairment: 12 13 Q. Okay. But you have no way then of saying with any kind of medical probability that it was due to this particular motor vehicle accident, as opposed to 14 all of his other prior brain injuries that he complained of where he also reported the same symptoms. Right? 15 A. The reason why I formed that opinion is because, based on the data that I have 16 now from the testing that I conducted with him and the impairments that are on the 17 test results, it seems as though the – his performance shows a, you know, difficulty in various areas of cognitive functioning that would have precluded him from 18 achieving the other more objective information that we have from his history, which is completing college, completing law school, and passing the bar, which 19 occurred after his reported head injuries from during the military.

20 Q. Well, how about the potential head injury from the other motor vehicle accident 21 he had?

22 A. It’s – again, that one was not documented as having had knowledge of him striking his head. 23 Q. How about the jiu jitsu head injuries? 24

25 A. I don’t have any data or information regarding the jiu jitsu head injuries other than what we saw in the records. So I don’t – it’s – I don’t know when they 26 occurred or what sort of affect they might have had on him.

27 Q. So then how can you rule out those head injuries as a potential cause of post- 1 A. Because he reportedly continued to do well in terms of his employment and 2 things like that prior to having gotten into the car accident.

3 Id. at 217:16-218:25. 4 Accordingly, the record at this stage of the proceedings reflects that: (1) the car accident 5 and pre-existing conditions both may have contributed to Plaintiff McLaughlin’s cognitive 6 impairment; and (2) Dr. Fratto has adequately supported his opinion that Plaintiff McLaughlin’s 7 current cognitive impairment is the result of the car accident. Thus, Dr. Fratto satisfies the 8 relevancy requirement as set forth in Daubert I, Daubert II and the Federal Rules of Evidence. 9 The Court therefore DENIES Tesla’s request to exclude Dr. Fratto’s testimony as irrelevant. Of 10 course, Plaintiffs still bear the burden of demonstrating to the jury that the car accident more likely 11 than not caused Plaintiff McLaughlin’s cognitive impairment. See Daubert II, 43 F.3d at 1320. 12 13 B. Dr. Fratto’s Testimony Is Not Unreliable The record reflects that, in 2019, Plaintiff McLaughlin reported to a medical-services 14 provider that he suffered from “headaches and multiple head injuries due to jiu jitsu activities.” 15 See Dkt. 78-3 at 183:17-185:9. Tesla argues that Dr. Fratto’s failure to consider these self- 16 reported head injuries renders his opinion regarding the cause of Plaintiff McLaughlin’s post- 17 accident injuries unreliable.5 See Dkt. 81-1 at 10-13. Plaintiffs counter that “no reliable evidence” 18 demonstrates that Plaintiff McLaughlin ever suffered an injury as a result of jiu-jitsu activities. 19 See Dkt. 85 at 8. They base their position on the absence of any medical record or opinion 20 reflecting injuries to Plaintiff McLaughlin of any kind, including head injuries, caused by jiu-jitsu 21 activities. See id. 22 Under Federal Rule of Evidence 702, an expert may testify only if their “testimony is 23 based on sufficient facts or data” and “is the product of reliable principles and methods.” See Fed. 24 R. Evid. 702(b)-(c). In evaluating the reliability of expert testimony, courts consider, inter alia, 25 26 5 Dr. Fratto testified, and Plaintiffs do not dispute, that Dr. Fratto did not consider Plaintiff 27 McLaughlin’s jiu-jitsu activities in rendering his causation opinion. See Dkt. 78-3 at 185:2-9, ] whether the expert accounted for alternative explanations: 2 3 Courts both before and after Daubert have found other factors relevant in determining whether expert testimony is sufficiently reliable to be considered by 4 the trier of fact. These factors include: ... [w]hether the expert has adequately accounted for obvious alternative explanations. See Claar v. Burlington N.R.R., 29 5 F.3d 499 (9th Cir. 1994) (testimony excluded where the expert failed to consider other obvious causes for the plaintiff's condition). Compare Ambrosini v. 6 Labarraque, 101 F.3d 129 (D.C. Cir. 1996) (the possibility of some uneliminated 7 causes presents a question of weight, so long as the most obvious causes have been considered and reasonably ruled out by the expert). 8 9 || Id. advisory committee’s note to 2000 amendment. 10 In light of this guidance, and based on the record at this stage of the proceedings, the Court 1] concludes that Dr. Fratto’s opinions satisfy the requirements of Rule 702. As discussed in Section 2 12 ILA, supra, Dr. Fratto addresses other obvious causes for Plaintiff McLaughlin’s condition. See 13 also Dkt. 78-3 at 217:16-218:25. He need not address every cause. Further, Plaintiff

14 McLaughlin’s self-reported head injuries, unsupported by medical records or opinions, do not 2 15 constitute such “obvious” alternative explanations or causes of his post-accident condition such 16 |) that failure to consider them renders Dr. Fratto’s opinion unreliable. Accordingly, the Court 17 || DENIES Tesla’s request to exclude Dr. Fratto’s testimony as unreliable. O 2 18 | Wn. CONCLUSION 19 For the foregoing reasons, the Court GRANTS IN PART and DENIES IN PART Tesla’s 20 requests to exclude the testimony of Drs. Andre and Fratto. 21 SO ORDERED. 22 || Dated: September 11, 2024 23 4 Sess yar 25 SUSAN VAN KEULEN United States Magistrate Judge 26 27 28