---
title: "Statistics Expert Witness’ Damages Calculation Limited Because She Included Extended Gap Periods in Her Analysis"
meta:
  "og:description": "Statistics Expert Witness had no basis for including Extended Gap Periods in the number of hours Prime Student Drivers potentially worked"
  "og:title": "Statistics Expert Witness’ Damages Calculation Limited Because She Included Extended Gap Periods in Her Analysis"
  author: "Expert Witness Profiler"
  description: "Statistics Expert Witness had no basis for including Extended Gap Periods in the number of hours Prime Student Drivers potentially worked"
---

# Statistics Expert Witness’ Damages Calculation Limited Because She Included Extended Gap Periods in Her Analysis

Posted on October 24, 2024 by Expert Witness Profiler

Defendant, New Prime, Inc., is a commercial trucking company, and its drivers are required to have a Commercial Driver’s License (“CDL”). It designates its CDL-licensed drivers as A seat, B seat, and C seat. B and C seat drivers are paired with an A seat driver until they attain enough experience to be an A seat driver and are paid less than A seat drivers.

Separately, Defendant created a program whereby individuals could receive the training necessary to obtain a CDL. This program has been referred to as the Prime Student Driver program, or “PSD program,” and participants have been referred to as “PSDs.” PSDs earn a Commercial Learner’s Permit (“CLP”) as part of that training, and at least some of those with a CLP drive a truck carrying freight for Defendant. Such PSDs are designated “D seat drivers” and must be accompanied by an A seat driver. PSDs are not paid, even when performing duties as a D seat driver.

Plaintiff, Peter Nyachira, asserted two claims. First, he alleged the failure to pay PSDs (or, perhaps, PSDs when acting as D seat drivers) violates the Fair Labor Standards Act (the “FLSA”) and Missouri’s Minimum Wage Law (the “MMWL”). Second, he asserted the amount paid to B and C seat drivers did not meet the FLSA’s minimum wage requirement.

One of the factual issues to be resolved is how much time B and C seat drivers worked. This issue is also relevant for PSDs if it is determined they were “employees” under the FLSA and MMWL. Another issue that must be resolved is whether the amount paid to B and C seat drivers satisfied the minimum wage requirements. Plaintiff retained [Liesl Fox](https://expertwitnessprofiler.com/expert-witness/Liesl-Fox/1548316) to testify on these matters.

## **Statistics Expert Witness**

[Liesl M. Fox](https://expertwitnessprofiler.com/expert-witness/Liesl-Fox/1548316) is a Senior Consultant and Partner at Quantitative Research Associates, a firm that provides statistical and computing consulting services, where she has been employed since 1997. She has been a statistical consultant for over twenty-five years, including conducting analyses in the fields of litigation and medical research, and has testified as an expert witness.

[Get the full story on challenges to Liesl M. Fox’s expert opinions and testimony with an in-depth Challenge Study.](https://app.expertwitnessprofiler.com/login?eId=1548316) 

## **Discussion by the Court**

#### **Basis for Estimates**

Fox’s estimates of the amount of time B and C seat drivers were working were called into question. To place the issue in context: drivers recorded their time in categories pursuant to the Department of Transportation’s Hours of Service (“HOS”) regulations.

The Court has already held in one of its previous rulings that the HOS categories did not correspond to time “worked” by drivers, and they therefore could not be relied on for that purpose. The Court further concluded drivers are working regardless of the HOS code that is entered and “this means that drivers engaged in multi-day trips are working 24 hours a day.”

Defendant argued Fox’s estimates did not sufficiently rely on the HOS logs. However, given the Court’s ruling, there is no basis for concluding Fox’s opinion should be excluded because she did not rely on the HOS logs more than she did.

#### **Allocation of Time**

Defendant retained its own expert, [Dr. Christopher Stanton, Ph.D](https://expertwitnessprofiler.com/expert-witness/Christopher-Stanton/1559735), to rebut Fox’s opinions and relied on his opinion to fault Fox for “assigning all time corresponding to the full duration of a trip that spans two weekly pay periods to the weekly pay period when the trip ended.”

It claimed this approach artificially inflates the number of hours worked in the second of the two weeks, creating a false impression that insufficient wages were paid for that week.

Plaintiff defended Fox’s approach by contending, essentially, that (1) Defendant’s records did not permit a different calculation method that is superior to the one she employed and (2) there is no artificial inflation of damages because Defendant pays drivers a set base amount each week.

The Court concluded that the dispute between Stanton and Fox did not affect the admissibility of Fox’s opinion. Defendant was free to cross-examine her on the issue, as well as present Stanton’s alternative calculation for the jury’s consideration.

#### **Starting Point for Calculations**

A collective action was certified under the FLSA for those claims, and a class was certified under [Federal Rule of Civil Procedure 23](https://www.law.cornell.edu/rules/frcp/rule_23) for the PSDs to assert an Missouri’s Minimum Wage Law claim.

The class definition for the collective action includes B, C, and D seat drivers who engaged in over-the-road training or team driving since May 9, 2020. The starting point for the Rule 23 class is also May 9, 2020. However, Fox calculated damages for the FLSA claims and the MMWL claims beginning on April 13, 2020, and May 3, 2020, respectively. Plaintiff defended this approach for the FLSA claims by arguing that if Defendant’s violation of the FLSA is willful, the statute of limitations is three years. He provides no explanation for the MMWL claim.

Defendant insists that the measure of damages is confined to the period described in the class definition. Neither party discusses the issue sufficiently to permit the Court to rule, so the Court defers ruling. Evidence of damages from before May 9, 2020, will not be permitted until the matter is resolved.

#### **“Blank” Codes for D Seat Drivers**

In addition to requiring drivers to record HOS time entries, Defendant maintained a calendaring system. Drivers are assigned various codes; for instance, “D” indicates they are under dispatch, and “A” indicates they are available for dispatch. In some instances, the calendaring system contains gaps; that is, there is not a code for every moment of every day. Fox defined an “Extended Gap Period” as one lasting 24 hours or more.

For B and C seat drivers, Fox compared the time covered by Extended Gap Periods to Defendant’s Duty Status Records; if the Duty Status Records indicated the B or C seat driver was working, Fox counted the Extended Gap Period as time for which compensation was due.

Fox treated PSDs differently. She compared the Extended Gap Period to the Duty Status record; then, if the Extended Gap Period ‘was associated with a calendar code . . . or had no calendar code, the gap remained in the analyses.’ Thus, even when confirming information was absent, Fox’s calculations assumed PSDs were working, despite neither the calendaring system nor the Duty Status records reflecting this. The Defendant argued there is no basis in the record for this assumption.

The Record establishes the calendaring system was not used for PSDs. Moreover, in her deposition, Fox conceded that 99% of the PSDs did not have any calendar codes, but she included the Extended Gap Periods because doing so is consistent with Plaintiff’s theory.

##### **PSDs were entitled to compensation for the Extended Gap Periods**

Plaintiff did not explain why PSDs were entitled to compensation for the Extended Gap Periods when (1) no available records suggested they were working during that time and (2) Extended Gap Periods were reflected in a calendaring system that is not used for PSDs. The Court concluded Fox had no basis for including Extended Gap Periods in the number of hours PSDs potentially worked, and therefore this component of her analysis must be excluded.

#### **Orientation Time for Certain B and C Seat Drivers**

Finally, Defendant argued orientation time for certain B and C seat drivers should be excluded. The Court need not consider Defendant’s argument because the Court granted Defendant summary judgment on Plaintiff’s claim regarding orientation. In other words, damage calculations for this aspect of Plaintiff’s claim were irrelevant and will not be admitted at trial.

## **Held**

The Court granted in part, denied in part and deferred in part the Defendant’ motion to strike the expert testimony of Dr. Liesl Fox.

The Court excluded Fox’s opinions regarding (1) Extended Gap Time for D seat drivers and (2) damages incurred by B and C seat drivers related to their attendance at orientation.

## **Key Takeaway:**

Based on Stanton’s alternative calculation, the Defendants claimed that Fox’s approach artificially inflates the number of hours worked in the second of the two weeks, creating a false impression that insufficient wages were paid for that week. However, the dispute between Stanton and Fox did not affect the admissibility of Fox’s opinion.

Fox conceded that 99% of the PSDs did not have any calendar codes, but she included the Extended Gap Periods because doing so is consistent with Plaintiff’s theory. The Court concluded Fox had no basis for including Extended Gap Periods in the number of hours PSDs potentially worked, and therefore this component of her analysis must be excluded.

## **Case Details:**

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