Plaintiff Azzine Kali alleged that while driving for Lyft on February 17, 2023, he was seriously injured in an automobile accident caused by the negligence of Defendant Erasmo Lopez, who at the time was operating his vehicle on behalf of Defendant J Bermudez Trucking, Inc.
Plaintiff produced the report of vocational rehabilitation expert John Dieckman, an assistant vocational services director at Proto-Worx, Inc. Defendants filed a motion to exclude Dieckman’s testimony.
Vocational Rehabilitation Expert Witness
John W. Dieckman, MS, CRC, CDMC has been a licensed vocationalist since 1983. He has been qualified as an expert vocationalist numerous times in both state and federal courts.
Defendants asserted that Dieckman’s opinion on Plaintiff’s future lost earnings should be excluded because it is speculative, subjective and unsupported by any published or unpublished sources.
Highlighting that Plaintiff cited no authority for his contention that vocational experts “routinely” employ BLS data, Defendants specify that in any event the issue here is that Dieckman did not apply a reliable methodology when he replaced Plaintiff’s actual job earnings as a rideshare driver with the government figure even though at his deposition he was unable to identify any literature or studies supporting this decision and admitted that “[t]here’s no particular way to confirm” that the selected Bureau of Labor Statistics (BLS) classification applies to Plaintiff.
The Court agreed with Defendants that Dieckman’s methodology in reaching his opinion regarding Plaintiff’s future lost wages was unreliable. Although Plaintiff’s earnings for his years as a rideshare driver for which Dieckman had complete information at the time of his report (2020 to 2023) ranged within a reasonably narrow band of a few thousand dollars each year, Dieckman jettisoned this data based on actual income in favor of the much higher (approximately 73 percent more than Plaintiff’s best year) BLS figure, despite the fact that he admittedly lacked key information regarding the applicability of the relevant BLS occupational classification, including what constituted “full-time” under it, the average number of days and hours worked, and whether the classification even covered rideshare drivers like Plaintiff.
B. “Fit”
Defendants asserted that Dieckman’s opinion that Plaintiff is limited to 50 percent of a normal workload (and thus 50 percent of his earning capacity) did not fit the facts of this case because his post-injury 2023 and 2024 tax records showed no diminution in his income.
The Court again agreed with Defendants. Dieckman’s findings are predicated upon the notion that Plaintiff will permanently remain able to work only half of a full workload, with an attendant 50 percent cut in earnings. However, after being injured in February 2023, Plaintiff went on to earn more as a rideshare driver that year than he did the year before and only $1,284 less than his all-time high from the year before that. Indeed, in 2024 (the most recent year for which there appears to be earning information), Plaintiff earned approximately 69 percent more than in 2022, the last full year before his injury. Yet Plaintiff asked the Court to permit Dieckman to testify that Plaintiff will never again reach more than 50 percent of his former earning capacity.
Held
The Court granted Defendants’ motion to exclude the testimony of Plaintiff’s expert, John Dieckman.
Key Takeaway
It is doubtful that Dieckman’s hypothesized final calculation is “testable” as to accuracy given that his choice of the BLS figure reflects a lack of “the existence and maintenance of standards controlling the technique’s operation.”
Case Details:
Case Caption:
Kali V. Lopez Et Al
Docket Number:
2:24cv4197
Court Name:
United States District Court, Pennsylvania Eastern
In July 2019, Plaintiff Amy Kessler was driving her car on Interstate 90 when she was rear-ended by a semitruck owned by Defendant McFarland Truck Lines, Inc. that, at the time, was being operated by Defendant Archie Gross within the scope of his employment with McFarland. As a result of the injuries she sustained in the collision, Kessler sued Gross and McFarland.
Kessler offered several opinions from her trucking expert, Walter Guntharp. With its motion to exclude, McFarland challenged those of Guntharp’s opinions that fell within the following three categories: accident causation, trucking industry hiring standards, and Gross’s driving history.
Trucking Expert Witness
Walter A. Guntharp has worked as a truck driver and a truck-driving instructor, and he has held multiple positions relating to safety in the trucking industry over the course of nearly fifty years.
Guntharp opined from his review of dashboard camera video capturing the incident that the accident was caused by Gross’s aggressive driving and failure to respond properly to the traffic conflicts produced by the construction zone. McFarland contended that Guntharp’s causation opinions must be excluded because he is not qualified as an accident reconstructionist and, even if he were, his causation opinions are not helpful to the trier of fact.
Although Guntharp is qualified to provide expert opinions on whether, in the lead up to the accident, Gross was driving in accordance with accepted industry safety standards, it did not follow that Guntharp also has sufficient expertise to opine on what caused Gross to collide with Kessler.
Even aside from Guntharp’s lack of expertise in accident reconstruction, the Court did not believe that his opinions on the cause of the accident would be helpful to the jury. In arriving at his conclusion that Gross’s unsafe driving was the cause of the crash, Guntharp relied mainly on the dashboard camera video of the accident. That same video will presumably be viewed by the jury. And Kessler will be free to offer Guntharp’s testimony about how Gross’s actions fell short of driving standards. But whether Gross’s substandard driving caused him to rear-end Kessler’s vehicle is a question better left solely to the jury. The jury is fully capable of considering the video footage in light of Guntharp’s testimony as to the applicable safe truck driving standards and determining causation for itself.
B. Trucking Industry Hiring and Retention Standards
To demonstrate that McFarland was negligent in hiring and retaining Gross as a truck driver, Kessler has offered several opinions from Guntharp about hiring standards in the trucking industry. McFarland challenged Guntharp’s qualifications to offer these opinions. Further, McFarland contended that Guntharp’s opinions on hiring and retention practices in the trucking industry are unreliable.
The Court concluded that Guntharp’s long experience in the trucking industry qualifies him to testify as to the industry’s practices for hiring and retaining truck drivers.
In attacking Guntharp’s methodology, McFarland focuses on his claim “that the standard in the trucking industry for hiring and retaining truck drivers is the ‘rule of three’: reasonably prudent motor carriers do not permit someone to drive a commercial motor vehicle if he has a combination of three or more moving violations and accidents in a three-year period.” McFarland contended that Guntharp’s assertion that the trucking industry adheres to a “rule of three” in hiring drivers is ipse dixit that lacks support from any reliable studies or data. The Court disagreed that Guntharp’s “rule of three” opinion is unsupported ipse dixit. Rather, Guntharp explained that his opinion is based on his years of experience in the trucking industry, as well as his review of the hiring and retention policies of thousands of trucking companies.
Finally, McFarland asserted that Guntharp’s “rule of three” is undermined by the data on which he relies. It highlighted how some of the trucking company policies that Guntharp reviewed do not automatically disqualify a driver whose preceding three-year record includes any combination of three moving violations and accidents but instead consider the seriousness of the accident or violation. However, that Guntharp’s “rule” might not be ironclad speaks to the correctness of his conclusions rather than the reliability of his methodology.
C. Gross’ Driving History
The final category of opinions that McFarland sought to exclude are Guntharp’s commentary on Gross’s prior accident history. Based on his review of Gross’s record of accidents and traffic violations, Guntharp opined that “Gross could not safely operate a commercial motor vehicle because of a lack of caution and attention while driving” and “routinely operated his truck in an aggressive manner that jeopardized the safety of others.” Kessler made no effort to defend these opinions. And the Court agreed that Guntharp’s characterization of Gross as an unsafe driver is pure ipse dixit. Rather than explain how the circumstances of each individual incident demonstrate Gross’s carelessness or aggressiveness, Guntharp seems simply to conclude that because Gross was involved in multiple preventable accidents and received multiple citations, he must have been an inattentive and overly aggressive driver.
Held
The Court granted in part and denied in part McFarland’s motion to exclude certain opinions of Kessler’s expert Walter Guntharp.
Key Takeaway:
The Court found that Guntharp is qualified to opine on driver hiring and retention practices in the trucking industry and employed a reliable terminology in concluding that trucking companies generally abide by a “rule of three” in considering a prospective driver’s history.
The Plaintiff, Neima Benavides, sued Tesla, Inc. after Naibel Benavides Leon was killed and Dillon Angulo was seriously injured when a Tesla Model S went through a T-intersection in Key Largo and off the pavement, striking their parked Chevrolet Tahoe as they were standing next to it.
George McGee, the driver of the Model S, had engaged the driver-assistance system, but had dropped his mobile phone and wasn’t watching the road while reaching for the device on the floorboard.
Mary “Missy” Cummings, an engineering professor at George Mason University is of the opinion that Tesla Inc. has fallen short in safeguarding against the dangerous misuse of its Autopilot system—raising serious concerns about safety and accountability on the road.
She also noted that even before the crash, Tesla was grappling with drivers routinely ignoring its system’s warnings. Yet, unlike other automakers, the company had resisted adopting geo-fencing technology that would prevent drivers from using Autopilot on roads where it wasn’t meant to be activated.
Systems Engineering Expert Witness
Mary Louise “Missy” Cummings was one of the U.S. Navy’s first female fighter pilots. She is now the director of Mason’s Autonomy and Robotics Center (MARC) and a professor at George Mason University. Cummings also holds faculty appointments in the Mechanical Engineering, Electrical and Computer Engineering, and Computer Science departments. She is an American Institute of Aeronautics and Astronautics (AIAA) Fellow and recently served as the senior safety advisor to the National Highway Traffic Safety Administration.
Cummings received her BS in Mathematics from the U.S. Naval Academy in 1988, her MS in Space Systems Engineering from the Naval Postgraduate School in 1994, and her PhD in Systems Engineering from the University of Virginia in 2004.
In a letter to NHTSA, Tesla asserted that “Autopilot has the most robust set of warnings against driver misuses and abuse of any feature ever deployed in the automotive industry.”
Cummings told the jury, “I saw no evidence that would back up this claim that they have the most robust set of warnings.”
Cummings has served as an expert witness in at least two other lawsuits against Tesla related to the Autopilot system, according to Court filings.
But when Cummings was appointed as a safety adviser to NHTSA in 2021, Elon Musk dismissed her as “extremely biased against Tesla,” sparking backlash from Tesla loyalists—some of whom even launched a petition to block her appointment.
The professor recalled that McGee was adamant—he believed the car was his copilot and would automatically stop for any obstacles. Like many Tesla drivers, she said, McGee placed his trust in Autopilot to take over when he dropped his phone, expecting the system to safely steer and react on its own.
Key Takeaway:
Safety expert Mary “Missy” Cummings took the stand with a sharp critique of Tesla’s Autopilot strategy, testifying that the company has failed to do enough to prevent drivers from misusing the technology. She pointed out that Tesla’s owner’s manual is difficult for drivers to access, and even before the crash, the company struggled with drivers ignoring critical computer-generated warnings. According to Cummings, Tesla made a calculated decision in 2019 not to geofence its technology—a move she believes was driven by the desire to boost sales rather than ensure safety.
This suit arises from a motor vehicle accident that occurred on September 7, 2018, in Vinton, Louisiana. Plaintiffs alleged that Billy Smith was operating a 2016 Kenworth T880 while traveling westbound on Interstate 10 on that date.
The vehicle was outfitted with Chinese-manufactured steel belt radial truck tires, distributed by CMA under the trade name “Double Coin tires.” The accident occurred when Smith’s tires suffered a catastrophic tread/belt separation, overturning the vehicle and severely injuring Smith. Smith passed away on September 4, 2021, and his surviving spouse and four adult children were substituted as Plaintiffs.
Defendants sought to introduce testimony from Dr. Richard W. Carr as an expert in the fields of trucking industry maintenance practices and trucking fleet and driver management standards. Carr offered opinions regarding alleged deficiencies in Smith’s licensure and driving conduct as well as in the maintenance of the vehicle and other practices by his employer, Kent & Smith Holdings, LLC.
Plaintiffs filed a motion to exclude Carr’s testimony under the standards set forth in Rule 702 and Daubert.
Transportation Safety Expert Witness
Richard W. Carr Ph.D., CDS is the principal of R W Carr, Inc., a Risk Management & Safety Consulting corporation based in Jacksonville, Florida, which primarily serves the transportation industry, construction industry, insurance industry, the legal profession, and the U.S. Government.
He has also worked as a Special Investigator and Accident Investigation Specialist for the Federal Motor Carrier Safety Administration. He has specialized training from the Federal Motor Carrier Safety Administration, Environmental Protection Agency, Penn State University, Northwestern University, Kennedy Western University, Georgia Tech, the National Nuclear Security Administration, and others.
Carr holds a Ph.D in Safety Engineering and has served as an expert witness in several cases over the last four years.
Plaintiffs did not challenge Carr’s qualifications but instead maintained that he lacked an adequate basis for the following opinions: (1) Billy Smith was not properly licensed at the time of the incident and failed to report vibrations in the steering wheel; (2) Kent & Smith lacked an adequate preventative maintenance program given their operational conditions; (3) Kent & Smith improperly allowed a plugged tire to remain in use; (4) Kent & Smith failed to retain and secure documentation post-accident relating to the subject vehicle and Smith; and (5) Kent & Smith’s alleged carrier violations four years after the accident are evidence of a culture of committing carrier violations around the time of the accident.
Smith’s Licensure and Failure to Report Steering Wheel Vibrations
In his deposition Carr opined that he “did not believe Smith had a valid CDL driver’s license at the time of this accident” because the copy contained in his Kent & Smith driver record had an expiration date of September 5, 2018, with no indication of renewal. Carr admitted, however, that he could not say one way or another whether the license had been renewed and that he had made no independent attempt to verify renewal. In response, Plaintiffs showed that a Class A CDL was issued to Smith on June 18, 2018, with expiration date of September 05, 2024.
Defendants maintained that Carr nonetheless had an adequate basis to reach his conclusion on Smith’s license status, based on the contents of his Kent & Smith driver’s record. Even if Smith was properly licensed at the time of the accident, the fact that his employer’s records indicated he was not may fall short of the standard of care. Further, they complained that the valid driver’s license is not Bates-stamped and was never produced in discovery.
The Court agreed that the record provided an adequate basis for Carr to opine that there was no evidence in Kent & Smith’s files at the time of the accident that Billy Smith was properly licensed.
Plaintiffs argued that Carr assumed based on defense expert Michael Grima’s report that the steering wheel was vibrating and then further assumed from the lack of documentation that Smith felt these vibrations and failed to report them.
The Court found that Carr is adequately qualified to opine on not just if but how Smith should have reported this effect—by formally recording it in his inspection reports. As he noted, the purpose of the reports was to identify issues so that they could be repaired.
Inadequate Preventative Maintenance Program
Carr also criticized Kent & Smith for failing to maintain an adequate preventative maintenance program. He based his assumptions about the lack of adequate maintenance on the extent of wear and tear visible on the tires in photographs. He could not cite an industry standard or state specifically how often Kent & Smith should have been inspecting the tires of its fleet, noting that he did not have a copy of the company’s maintenance schedule. Instead, he described his own experience operating a truck over gravel and how it necessitated replacement of the tires after only 50,000 miles.
While Plaintiffs write this off as anecdotal, the Court held that Carr’s experience is highly relevant to the tires at issue and their working conditions, and he applied this lens when reviewing the photographs and maintenance records.
Allowing a Plugged Tire to Remain in Use
Carr noted that the right front steering tire had been plugged at least three times. Plaintiffs challenged this opinion because Carr never conducted a firsthand examination of the subject tire. But Carr reviewed photographs as well as the report of Grima, who found evidence of prior punctures.
As Defendants noted, “[e]very expert who has reviewed the tire has noted the numerous punctures on the tire, the stone drilling in the tire, and the wear of the tire. These facts are not in dispute.” In other words, Carr’s extrapolation, based on testimony that Plaintiffs failed to refute, that leaving such a tire on the steering axle violated Kent & Smith policy appeared to be on solid footing.
Failure to Retain and Secure Documentation
In his deposition Carr pointed to deficiencies in Kent & Smith’s record retention. Plaintiffs then pressed him as to whether any such failures contributed to the accident. Carr responded: “By them not providing documents, it did not contribute to the cause of the accident, but it might have inhibited or changed opinions, or aided in the scope and process of the ongoing litigation related and caused by the accident.”
Plaintiffs objected that this opinion was irrelevant because, as Carr admitted, any record retention deficiencies did not cause the accident. But, as he explained, the absence of records could have inhibited investigation of the accident and a discovery of its contributing factors. Additionally, the Court held that Carr is adequately qualified through his industry experience, including a stint as an investigator for the Federal Motor Carrier Safety Administration (“FMCSA”), to reach this opinion.
Kent & Smith’s Culture
Finally, Carr asserted in his deposition that Kent & Smith had a “culture” of violating safety regulations based on its record from August 2022 to August 2024. Plaintiffs thus moved to exclude this opinion, arguing that testimony regarding Kent & Smith’s subsequent violations is prohibited under Federal Rule of Evidence 404(b).
Defendants made no argument in support of the relevance of the subsequent violations. The Court agreed that, even if they were offered for some purpose under Rule 404(b) other than showing Kent & Smith’s bad character, they have no probative value because they occurred four to six years subsequent to the subject accident. The motion is therefore granted to the extent that Carr is prohibited from referencing these violations or opining on Kent & Smith’s safety culture at the time of the accident based on its 2022-2024 record. This limitation, however, did not prevent Carr from opining on Kent & Smith’s compliance with DOT and FMCSA practices at the time of the accident based on other, more contemporaneous records.
Held
The Court granted in part and denied in part the Plaintiffs’ Daubert motion to exclude the testimony of Defendants’ expert Richard W. Carr.
Key Takeaways:
Experts are permitted to rely on their own relevant experience—including anecdotal cases. It is the responsibility of opposing counsel to explore the factual basis for the opinion and thus, determine its reliability.
An expert may rely on hearsay, including other expert reports, in forming his opinions. Although the Court found that Grima lacked an adequate basis for his main conclusions and that his testimony would not be helpful for the jury, there is no basis to doubt his findings as to the effects that the tire’s condition would have on the vehicle’s operations. Likewise, Carr was adequately qualified to opine on not just if but how Smith should have reported this effect—by formally recording it in his inspection reports.
Please refer to the blog previously published about this case:
This action arises out of a motor vehicle accident between an automobile driven by Philnelius Snow and a tractor-trailer owned and operated by Charles Bailey Trucking (“CBT”)and driven by its employee, Travis Hickey. Plaintiff alleged two causes of action against CBT: 1) respondeat superior for the negligence of its employee, and 2) direct claims of negligence against CBT for negligent hiring, negligent training, negligent entrustment, negligent retention, negligent qualifying, and negligent supervision of Hickey (Plaintiff’s “Direct Negligence Claims”). Defendants argued that they are entitled to summary judgment on the Direct Negligence Claims and Plaintiff’s punitive damages claim.
Defendants filed a motion to exclude Plaintiff’s expert Adam Grill‘s testimony about CBT’s responsibilities as a motor carrier and the negligent training claim.
While parties occasionally file Daubert motions alongside summary judgment motions, such motions typically implicate a summary judgment issue such as causation. Here, the only issue on summary judgment relates to negligent training. The Court will consider Defendants’ motion to exclude Plaintiff’s expert Adam Grill’s testimony as it relates to CBT’s responsibilities as a motor carrier and the negligent training claim only, and finds it premature to address other potential issues at this time.
Trucking Expert Witness
Adam Grill has worked around large commercial vehicles and studied the intricacies of commercial vehicle transportation among the best in the industry. He received his certification as a commercial vehicle operator in 2005. He holds a Commercial Driver’s License (CDL) with endorsements for hazardous materials, tankers, double trailers, triple trailers, passenger buses, and school buses. Grill is a certified director of safety (CDS).
He is certified for forklift operation, operation of longer combination vehicles (LCVs), crane hoist and rigging, aerial manlift, telehandler, and heavy equipment including payloaders and motor graders. Grill is a certified pilot car operator and flagger through Gulf Coast Community College in Panama City, Florida. He is currently an active truck driver, and an associate of Atlantic Pacific Resource Group.
Grill’s expert report contended that “Charles Bailey is responsible to train and supervise their professional drivers” and “[a]ccording to industry standards, this collision was preventable on the part of Charles Bailey and Defendant Hickey.”
Defendants argued that the expert report and proposed testimony should be excluded because Grill’s opinions are not reliable and his testimony would not assist the trier of fact because his opinions merely offer legal conclusions.
Defendants argued that “Grill’s report merely regurgitates the Federal Motor Carrier Safety Rules (“FMCSRs”) and states that [CBT] failed to comply with the law.” According to Grill, CBT did not provide specific training to drivers on “visual search techniques” and if it had, then the collision between Snow and Hickey could have been prevented.
Grill asserted that CBT failed to satisfy the FMCSRs related to training. Grill’s testimony further asserted that:
A. Because the specific concepts involved in leading up to this accident, through proper education, training and including the proper mindset of a driver, it would be completely avoidable. In other words, the reasonable expectation of a driver to keep a proper visual search, have a plan, an advance plan for how to respond to hazards, would in a practical sense and through the testimony of the driver in this case, would have — would have allowed him to prevent this type of collision from occurring.
The Court held that Grill’s testimony that additional training would have prevented the collision is unreliable speculation and does not help the Court determine whether Plaintiff has met his burden as a matter of law.
Held
The Court excluded Adam Grill’s expert report and proposed testimony for the summary judgment motion. It granted in part Defendants’ motion for partial summary judgment as to Plaintiff’s claims of negligent hiring, negligent retention, negligent qualifying, negligent supervision, negligent entrustment, and punitive damages.
Key Takeaway:
A negligent training claim requires a showing that (1) the employer’s training was deficient, and (2) breach of that duty proximately caused Plaintiff’s injury. The Court is capable of referring to the FMCSRs and relevant case law to determine whether CBT’s training was legally deficient. Moreover, Grill’s testimony that additional training would have prevented the collision is unreliable speculation.
Case Details:
Case Caption:
Snow V. Charles Bailey Trucking, Inc. Et Al
Docket Number:
1:22cv706
Court:
United States District Court for the Northern District of Georgia, Atlanta Division
A district judge in Texas allowed a truck safety expert to testify about safety regulation compliance after stating that his testimony did not consist of methodological flaws.
Plaintiff Antoine Manson alleged that on March 20, 2021, at about 3:00 a.m., he was traveling on Loop 1604 in Bexar County, Texas when he was struck by Defendant Mariel A. Arias-Padilla (“Defendant Driver”), who was driving a commercial motor vehicle within the course and scope of her employment with Defendants B&S Trucking of Jackson, LLC (“Defendant Company”) and JJ&C Express Corp.
The force of the impact allegedly caused Plaintiff to lose control and subsequently crashed into the median concrete barrier. Plaintiff alleged that he suffered major injuries as a result.
Plaintiff sought to exclude the testimony of Rodney Ellis, Defendants’ expert witness. The Defendants designated Ellis as a commercial vehicle safety and safety regulation compliance expert. The Defendants stated that Ellis may testify regarding “commercial vehicle safety, hiring, training, supervision, risk management, loss prevention, regulatory compliance, operations, driver qualifications, driver safety procedures, hours of service regulations, and driving techniques.”
Safety Expert Witness
Rodney Dean Ellis II has been involved in the trucking industry as a licensed commercial truck driver and safety consultant since 1991, performed “dozens of audits of commercial motor carriers/shippers,” and received professional training by several transportation associations.
Plaintiff did not appear to challenge Ellis’ qualifications to testify. Rather, Plaintiff disputed Ellis’ conclusion that while Defendant Driver “was in off duty status, the global positioning data in the driver log records indicated that she had a co-driver who drove the tractor-trailer while she was off-duty.”
Plaintiff asserted that in reaching this conclusion, Ellis ignored key evidence including i) the driver logs do not indicate a co-driver; ii) Defendant Driver provided conflicting deposition testimony regarding the presence of a co-driver; and iii) the police report does not indicate the presence of such a co-driver.
Defendants countered that Ellis relied on several parties’ depositions (including Defendant Driver), driver logs, global positioning data contained within the driver logs, and an “Interview with [Driver Defendant] Mariel Arias-Padilla.”
Based on this information, Ellis testified he concluded there was evidence of a second driver because there was no unidentified driver movement of the vehicle in the logs, supporting that another driver with identifying credentials was logged into the system; that the logs contained no error messages consistent with Defendant Driver logged out but no other driver logged in; and that the data shows another driver logged into the database, though it does not specify which driver.
Moreover, the Court held that the Plaintiff did not identify any methodological flaws with Ellis’ work. Rather, Plaintiff pointed to extrinsic evidence—such as conflicting testimony from Defendant Driver or the police report—to undercut Ellis’ interpretation of the driver logs.
In conclusion, the Court found Ellis’ opinion reliable, because the driver logs were crucial in determining whether Defendant Driver was fatigued at the time of the accident.
Held
The Court denied the Plaintiff’s motion to exclude Defense Expert Rodney Ellis.
Key Takeaway:
The Court, citingHolcombe v. United States, 516 F. Supp. 3d 660, 675 (W.D. Tex. 2021), held that an opposing party’s “doubts about the bases” of an expert opinion did not render an expert opinion “unsupported,” and such questions affected “the weight to be assigned to that opinion rather than admissibility.”
