Category Archives: Expert Opinions


Expert Testifies Flint Death Not Legionnaires’ Disease

An infectious disease expert has testified that a Flint-area man who died in 2015 did not die from Legionnaires’ disease.

Flint Legionnaires’ Crisis

In 2014 and 2015, a Legionnaires’ outbreak in the Flint area killed 12 people and caused at least 79 others to become ill.  The State of Michigan charged its state chief medical officer Eden Wells with involuntary manslaughter in connection with the deaths.  Wells is also facing charges of lying to a special police agent, misconduct in office, and obstruction of justice.  The manslaughter charge carries a prison term for up to 15 years and a $7,500 fine. The obstruction charges carries a sentence of up to two years.  Governor Rick Snyder kept Wells in her post despite the criminal charges against her.

Expert Testimony

At trial, Wells’ defense team called Dr. Jeffrey Band to testify as an expert witness. Dr. Band is an epidemiologist who works at Beaumont Hospital in Royal Oak, Michigan.  Dr. Band reviewed the patients’ records to prepare his testimony.

Dr. Band testified extensively about the 2015 death of John Snyder.  Band opined that Snyder’s death was not Legionnaires’ disease. Band said that he “absolutely” considered that Legionella could have been the cause of death, but he was ultimately able to determine that it was not the cause.  Band stated that Snyder suffered from rheumatoid arthritis, which can cause a person to exhibit “false positives” for Legionella.

Dr. Band stated that Snyder’s records showed that he declined his doctor’s request to replace his pacemaker with a defibrillator, which meant that Snyder was “at risk for sudden death.”  Band noted that Snyder did not have a fever, which is a symptom of Legionnaires’.  He said, “He was not found to have an elevated white count. With Legionnaires’ disease, one of the features is a very high fever and it’s unremitting. It stays up there. And Mr. Snyder did not have any fever.”  Band testified that Snyder’s heart was “down to, at most, 30 percent functioning” and that he also suffered from “bilateral density in the lungs,” which caused additional problems.

On cross-examination, Special Prosecutor Todd Flood asked Band when the public should be notified about a deadly disease.  Band testified that the 2014-2015 Legionnaires’ diagnoses constituted a “smoldering outbreak” with a small number of cases over a period of time. Band opined that the public did not need to be notified because it would cause a panic as the disease cannot be treated by a vaccine like other diseases.  Flood noted that Band’s opinion was counter to the doctors from Wayne State University who testified that the public should have been notified of the outbreak.

Band revealed that he was compensated $400 per hour for his time, for a total of approximately $19,000.  Band stated that he resented Flood’s assertion that he was being “paid” for his opinion.  Flood stated that, “I’ve never implied that the Legionella situation in Genesee County was not significant.”

A gun in a car seat

Judge Allows Re-Deposition of Police Procedures Expert

A judge has ruled that the defense attorneys for Nouman Raja will be allowed to re-depose the state’s expert on police procedures.

Corey Jones’ Shooting

Nouman Raja, a former Palm Beach Gardens police officer, is on trial for manslaughter and attempted murder in connection with the 2015 shooting death of 31-year-old Corey Jones.

On October 18, 2015, Jones was stranded on the side of the road and on the phone with roadside assistance. Officer Nouman Raja approached Jones in plainclothes. Raja was wearing jeans, a T-shirt, a ball cap and driving an unmarked cargo van.

Jones died after Raja shot him three times. Raja claims that he clearly identified himself as a police officer and that he only shot Jones after he charged at him with a gun. However, an audio recording of Jones’ call with the roadside assistance operator contradicts Raja’s version of the events. Additionally, a 911 call that Raja made raised questions because Raja is heard yelling at someone to drop a gun, but medical examiner’s reports revealed that Jones was likely dead at the time that Raja made the 911 call.

Expert Witnesses

The state presented W.D. Libby as an expert on police procedures. Libby has spent 38 years in law enforcement; 16 of those years were spent as a police chief. Libby has a law degree and is experienced in overseeing police standards.

In Libby’s report, he opined that Raja acted incorrectly when he approached Jones’ broken-down SUV while he was working plainclothes on burglary surveillance. Libby stated that, by parking in front of Jones, Raja left his vehicle “in such a position that it did not protect him or Corey Jones.” Libby opined that Raja should have parked behind Jones and called for backup.

Libby also opined that Raja failed to follow proper procedures by approaching Jones. Libby cited the International Association of Chiefs of Police recommendation that plainclothes officers “present proper identification. If requested, let the driver examine your credentials so that they are satisfied that you are a law enforcement officer.”

Libby stated that Raja acted in violation of supervisor’s orders by failing to wear a tactical vest, which would have identified him as a police officer. Libby said that Raja “did not verbally announce who he was, why he was there, or indicate police authority, violating accepted police practice.”

Raja’s attorney, Scott Richardson, challenged the consistency of Libby’s opinion. He said, “We felt there was an inconsistency, a discrepancy between what the state’s expert witness had testified to and what was said later in another deposition.” Richardson also questioned whether the state had been withholding information about Libby’s opinion on whether use of force was justified in this case.

Judge Samantha Schosberg Feuer decided that defense attorneys will be allowed to re-depose Libby. Richardson will be allowed to ask Libby about his opinion on whether use of force was justified in this case, when he formed that opinion, and when he disclosed that opinion to the state. Libby previously opined that, “I do not believe the forensic evidence supports [Raja’s] version of events.”

Raja’s attorneys plan to file a separate motion to have Libby’s testimony excluded entirely.

Empty Hall

Expert Testifies That Coolers Made Conditions Worse in Nursing Home

An air-conditioning engineer has testified that the portable air conditioning units in a Florida nursing home where twelve elderly patients died of overheating made the conditions worse.

The Deaths

The Rehabilitation Center at Hollywood Hills is a 150-patient facility that lost its main air conditioning system during Hurricane Irma. The system was knocked out on September 10; by September 13, patients began dying and the facility was evacuated. Twelve patients died as the result of overheating. The deaths were ruled homicides. Authorities say that the temperature in the home reached dangerous levels, despite the nine portable air conditioners that were deployed after the main system was knocked out. Florida law requires nursing homes to maintain a temperature of 81 degrees or less.

The Lawsuit

Following the deaths, Governor Rick Scott ordered the state Agency for Health Care Administration (AHCA) to prevent the home from taking on new residents. AHCA also stopped Medicaid patients and eventually pulled the Rehabilitation Center’s license, alleging that the Rehabilitation Center presented a threat to public health, safety, or welfare and that “deficient practices exist presently and will more likely than not continue to exist if the agency does not act promptly.” The Rehabilitation Center closed its facility and laid off 245 employees.

The nursing home filed a lawsuit against the state, seeking injunctions against AHCA’s orders. The Rehabilitation Center claimed, “With the stroke of a pen, AHCA (the Agency for Health Care Administration) has effectively shut down Hollywood Hills as a nursing home provider in Broward County. . . . These illegal and improper administrative orders took effect immediately and without any opportunity for the facility to defend itself against unfounded allegations.”

The state hired William Crawford, an air-conditioning engineer, as an expert witness. Crawford offered testimony in the form of a deposition before the Rehabilitation Center’s attorney, Geoff Smith. Crawford testified that the portable air conditioners used by the home were insufficient and that they only produced about 10 percent of the cooling capacity of the home’s central air conditioner that was knocked out by the storm.

Crawford testified that the air conditioners were not properly vented. Air conditioners function by taking hot air from an enclosed space and moving it outside. The Rehabilitation Center’s first floor portable air conditioners vented the hot air to the ceiling, which meant that the first floor’s hot air went to the second floor and back to the first floor. Crawford testified that the air temperature between the first-floor ceiling and second floor floor ranged somewhere between 95 degrees and 110 degrees.

Crawford said that the improper ventilation of the air conditioners caused the temperatures within the building to increase. He said, “I can say with certainty it was above 81” in most of the facility. He conceded that it was possible that it was cooler within the 9 feet of the five portable units that were on the first floor; however, he asserted that “There was no way they maintained 81 degrees on the second floor.”


Judge Allows Expert Testimony in Carnival Cruise Lines Negligence Case

A federal judge has ruled that two expert witnesses for the plaintiff will be allowed to testify in a negligence lawsuit against Carnival Cruise Lines and its partners.

The Incident

In 2015, David Carideo was on an electronic music themed “Groove Cruise” run by Carnival Cruise Lines and Whet Travel Inc. During this cruise, alcohol was sold both on the ship and  during shore excursions. Carideo alleges that he was attacked by two of his fellow passengers. Carideo claims that his attackers threw him to the ground and beat him, resulting in a fractured skull and permanent injury to his head. A Carnival security officer who was patrolling the deck above heard the altercation and responded to the scene, but by the time he arrived, Carideo had already been beaten.

Expert Witnesses

Carideo filed a negligence suit against Carnival and its partners in the U.S. District Court in the Southern District of Florida. Carideo claims that the attack was fueled by alcohol. He alleges that Carnival and Whet Travel benefited financially from selling alcohol in profuse quantities and that security measures were insufficient to ensure passenger safety. Carideo claims that the Groove Cruise was “three days of partying, billed as an electronic music dance party” where passengers “became intoxicated to the point of vomiting around the ship and reaching points of inebriation, such that they became physically ill.”

Carideo retained Dr. Ross Klein and Howard Wood to testify as expert witnesses. Dr. Klein is sociologist who the plaintiff retained to testify as an expert on the cruise industry and plans to offer testimony on the foreseeability of crime on a cruise ship. Wood is a security and counterterrorism expert who will testify about Carnival’s security measures and its ability to prevent crime onboard its ships.

Carnival filed a Daubert motion, challenging the testimony of both proposed experts. In the motion, Carnival argued that Dr. Klein and Mr. Wood’s opinions were not supported by a reliable methodology and that they were based on lack of applicable expertise. Carnival noted that Dr. Klein did not have any academic training in law enforcement, criminology, security, criminal investigations, or tourism. Carnival challenged Mr. Wood’s opinions because his report did not explain how or why his experience led to an acceptable and reliable methodology and because his report was full of advocacy.

Carnival essentially asked the court to rule whether a person can testify as an expert witness if he or she has no formal academic training or actual work experience in the field, but instead obtained knowledge through research and review.

U.S. Magistrate Judge Jonathan Goodman ruled that Dr. Klein and Mr. Wood will be allowed to testify and stated that any doubts that the defendants have about the expert’s credibility are best addressed during cross-examination. In his order, Judge Goodman stressed that “a less-than-perfect expert opinion may still be admitted, even if it contains gaps” and noted that the court “must be careful not to conflate questions of admissibility of expert testimony with the weight appropriately to be accorded such testimony by the fact finder.”


Ballistics Expert Testifies in Trial About Teen’s Shooting

A ballistics expert has offered testimony in the federal lawsuit over the fatal shooting of 17-year-old Justus Howell that happened in 2015.

The Shooting

In April 2015, Zion police officer Eric Hill responded to reports of a fight between two men and gunshots. According to authorities, Justus Howell had been trying to steal a semi-automatic pistol from a man from whom he had originally arranged to purchase it. A surveillance video shows the two men fighting, Howell pointing the gun at the other man, the man pushing the gun away, and the gun discharging.

Officer Eric Hill arrived on the scene. Hill claims that after a short chase and telling Howell to stop, he saw a flash of silver in Howell’s hand that he determined to be a gun. Hill says that he feared for his life and the lives of the other officers, so he shot Justus Howell two times.

In May 2015, Lake County State’s Attorney Michael Nerheim found that Officer Hill’s use of force was justified.

Trial Testimony

Howell’s grandmother sued Hill and the city of Zion for damages, claiming that Officer Hill acted recklessly and with excessive force when he shot her grandson. The attorney for the plaintiff argued that Hill covered up his actions after the shooting and that he “doctored” the scene. The plaintiffs argue that the gun found on Howell was in his pocket and later placed on the grass.

Attorneys for the plaintiff retained Ronald Scott as an expert witness. Scott is a forensic ballistics expert who has served 25 years with the Massachusetts State Police. Scott reviewed all of the documents related to the shooting, the surveillance video footage, and Hill’s personnel files. Scott testified that he “consider[ed] [Hill] to be an above-average trained police officer.”

Scott testified that the forensic evidence and the surveillance video show that Howell was nearly doubled over when he was shot by Hill. This would be inconsistent with Hill’s statement that he fired at Howell after he had turned a gun on him.

Scott also testified that he was able to determine Hill’s approximate position during the shooting by analyzing the shell casings that were found at the scene and Howell’s autopsy. Scott testified that Hill shot Howell and the bullets entered his body diagonally from the left to the right.

Scott also noted that the surveillance video did not show a reflection of a gun or light-colored object in Howell’s hand. The gun that was found at the scene had a silver finish.

Defense attorney Thomas DiCianni questioned Scott’s credibility and testimony. DiCianni cited to a deposition whether lawyers hired him to “bust a hole” in Hill’s testimony. Scott replied that his responsibility is to the evidence. DiCianni cited a forensics handbook on police shootings that said that shell casings were unreliable evidence. DiCianni also pointed out the the gun found at the scene had a matte finish, so would not have flashed in the video footage.


The jury evidently rejected the expert testimony. It returned a verdict in favor of the defense, finding that the evidence failed to establish that Hill used excessive force.


Monsanto Judge Rules Expert Opinions Are “Shaky”

The federal judge presiding over the high-profile Monsanto Roundup lawsuit has determined that the experts testifying against it have “shaky” opinions.

The Lawsuit

Monsanto is being sued by multiple parties who claim that the active ingredient in its herbicide Roundup, glyphosate, has caused non-Hodgkins lymphoma. The lawsuits were consolidated into a multidistrict case in San Francisco presided over by U.S. District Judge Vince Chhabria. This case includes over 700 farmers, landscapers, and gardeners who claim that their non-Hodgkin lymphoma was caused by exposure to glyphosate.

Glyphosate/Roundup is the most widely used agrichemical. It was introduced by Monsanto in 1974 and its use exploded in 1996 when Monsanto introduced “Roundup-ready” seeds that were engineered to resist glyphosate.

Expert Testimony

Judge Chhabria held a causation hearing and heard testimony from numerous experts including toxicologists, statisticians and an oncologist. Judge Chhabria was particularly interested in testimony from the epidemiologists, who study how human contract diseases. Judge Chhabria said, “I do have a difficult time understanding how an epidemiologist in the face of all the evidence that we saw and heard last week” can conclude that glyphosate “is in fact causing” non-Hodgkin lymphoma in humans. “The evidence that glyphosate is currently causing NHL in human beings” at current exposure levels is “pretty sparse.”

All but one of the plaintiffs’ experts relied upon a 2015 study conducted by the World Health Organization’s International Agency for Research on Cancer (IARC). The IARC study concluded that glyphosate is a probable carcinogen. Judge Chhabria said that the IARC study alone was not enough to argue that the glyphosate is more likely than not to be the cause of plaintiffs’ cancer. Other studies, including a 2017 review by the U.S. Environmental Protection Agency, have concluded that glyphosate is not a carcinogen. The attorney for the plaintiffs, Brent Wisner, argued that the judge should not reject experts because they relied on the IARC report and that he should dissect and consider the “subset of opinions” contained within their reports.

One of the plaintiffs’ experts conducted her own independent analysis. UCLA epidemiologist Dr. Beate Ritz testified that she reviewed over a dozen cases and was able to conclude “to a reasonable degree of scientific certainty” that glyphosate causes cancer in humans. Judge Chhabria called Dr. Ritz’s conclusion “dubious,” but questioned  whether it was “outside the range of a reasonable scientific conclusion that epidemiologists can draw?”

Attorney for Monsanto, Eric Lasker, argued that Dr. Ritz’s testimony should be rejected because her findings were based on “unadjusted odds ratios” and “confounded data.” Attorney for the plaintiffs, Aimee Wagstaff, said that their experts took confounding into consideration and that each expert considered both unadjusted and adjusted odds ratios.

Judge Chhabria concluded that epidemiology is “loosey-goosey” and a “highly subjective field.” However; Judge Chhabria did indicate that Dr. Ritz may be allowed to testify in front of a jury. He said, “Maybe Dr. Ritz, despite some of the problems with her testimony, is operating within the mainstream of the field. . . , Maybe it’s up to the jury to buy her presentation.”


DNA Expert Plays Key Role in Exoneration Hearing

A DNA expert has offered critical testimony in the exoneration hearing of Freddie Joe Lawrence and Paul Kenneth Jenkins.

The Crime

Freddie Joe Lawrence and Paul Kenneth Jenkins are serving life sentences after being convicted of killing Donna Meagher in 1994. Meagher was killed when she was closing up a family-owned bar and casino in Montana City.

New Evidence

The Montana Innocence Project got involved with the case post-conviction and some of the evidence from the crime scene was sent away for DNA testing. The DNA tests linked another man, David Wayne Nelson, to the crime. Nelson is currently serving a life sentence after pleading guilty to killing two people in Deer Lodge in October 2015. DNA tests on the rope found close to where Meagher was killed showed both Meagher’s blood and Nelson’s DNA.

Separately, the state reopened its investigation into Meagher’s murder after David Nelson’s former sister-in-law and nephew told authorities that Nelson had confessed to Meagher’s murder in 1998. Nelson denies these claims and having anything to do with Meagher’s death.

Exoneration Hearing

To overturn their convictions, Jenkins and Nelson will have to show that there is a reasonable probability that the outcome of the trial could have been different if a new piece of evidence was introduced.

Dr. Greg Hampikian, Ph.D. of Boise State University testified as an expert for the defense. Dr. Hampikian testified that there is no DNA evidence linking Jenkins or Lawrence to the crime and that a key piece of evidence matched another male. Hampikian used a technique called probabilistic genotyping to determine that there is a one-in-700 billion chance that the DNA testing excluding Lawrence’s from the site is wrong. In Jenkins’ case, the chance is one in hundreds of thousands. Hampikian explained that anything more than a thousand is very strong evidence that the DNA does not match. Hampikian testified that Nelson’s DNA was almost a direct match, “It’s about as strong of a match as I have ever seen.” He said that the probability of the DNA not being Nelson’s is 1-in 10 septillion.

Nelson was subpoenaed to testify at the hearing, but exercised his right to remain silent.

Montana state court Judge Kathy Seeley presided over the hearing and did not make her ruling from the bench. She stated that she would take the parties’ arguments under advisement.


Meagher’s family has stated that reliving the trauma from the crime is painful. Meagher’s daughter Michelle has said that she felt that the state had substantial evidence against both men. She noted that, “Independently, 24 people decided they were guilty. . . . Our family is re-living the trauma from the crime and this is unexplainable to someone who has not gone through something of this magnitude.” Larry Mansch, legal director for the Montana Innocence Project, has said that the family’s pain is understandable and that, “this is a terrible thing that happened to Donna. . . . We are trying to figure out who the perpetrator was.”

Lab Analysts May Be Required to Testify in Person in Criminal Trials

Experts Battle Over Validity of DUI Blood Tests

Experts contest the validity of retrograde extrapolation in the DUI trial of Cody Austin Shirah.

The Crash

In September 2016, a group of Ohio softball players were in Bay County, Florida for the World Sports League World Softball Championships. As they were on their way back to their hotel from their tournament, Cody Austin Shirah ran a stop sign and crashed into their minivan. Two of the men died at the scene; two other died as a result of their injuries from the crash.

Shirah was charged with four counts of negligent manslaughter involving a motor vehicle, or DUI manslaughter, and driving without a license.

The Blood Tests

Carol Seagle, a toxicology analyst with the Florida Department of Law Enforcement, testified that a sample of Shirah’s blood was taken about 3 hours and 45 minutes after the crash.  Shirah’s blood had a blood alcohol content of 0.078 percent. The legal limit is 0.08. Seagle testified that Shirah’s blood alcohol content was likely between 0.09 percent and 0.14 percent at the time of the crash.

Barry Funk, a forensic toxicologist for the defense contested the methods that Seagle used to reach her conclusion. Funk explained that the process of retrograde extrapolation involves too many factors to be trusted, including medical history, injuries, and medicines that have been taken. Funk said, “All things have to be taken into consideration with retrograde extrapolation. . . . You can’t count them out as factors. It makes a difference to conclude what alcohol content would’ve been at the time of the incident.”

Despite Funk’s attempt to question the validity of the use of retrograde extrapolation, the prosecutor was able to elicit Funk’s admission that the blood drawn at the hospital one hour after the crash amounted to 0.125 percent alcohol content. Additionally, Shirah’s girlfriend, who had been a passenger in his truck had a blood alcohol content of 0.145 percent. Since the girlfriend was not driving, however, the relevance of that evidence is unclear. There were also beer cans found around the area where Shirah’s truck had overturned.

Retrograde Extrapolation Explained

The use of retrograde extrapolation to determine blood alcohol content is based on the assumption that people eliminate alcohol at a fixed rate of between 0.01 grams and 0.02 grams per deciliter of blood per hour. For a retrograde extrapolation calculation to be accurate, a person must metabolize alcohol at the normal rate and the person must be in the postabsorption phase, which typically occurs 15 to 90 minutes after a person’s last drink.

However, each person’s absorption rate varies. Many factors, including the type and amount of food eaten, the type of alcohol consumed, and the length of time over which the drinking occurred will affect the rate of absorption. Because retrograde extrapolation is uncertain, blood alcohol test results are only presumed to be valid if the blood sample is drawn within three hours after the test subject was driving. The longer the delay in obtaining a test sample, the more speculative those conclusions are likely to be. As a general rule, expert evidence is required to establish a blood alcohol content when more than three hours have lapsed since driving ended.


False Confessions Expert Testifies in Homicide Trial

False confessions expert Alan Hirsch offered testimony for the defense in the murder trial of Bobby Griffin Jr.

The Crime

On October 14, 2013, Nathaniel Bradley was fatally shot as he stood outside his car in New Haven, Connecticut. Bobby Griffin Jr. was charged with felony murder, murder, attempted first-degree robbery, and conspiracy to commit first-degree robbery in connection with Bradley’s death.

While Griffin initially admitted to murdering Bradley, he later claimed that he was coerced into confessing by the police who interrogated him. Griffin now claims that he was present for the crime but another man was the shooter.

The Trial

Griffin’s attorneys argued that the jury should hear about false confessions because the police detectives coerced Griffin into falsely confessing that he shot Nathaniel Bradley.

Griffin’s attorney presented Williams College professor Alan Hirsch to testify as a false confessions expert. Prosecutors Sean McGuinness and John P. Doyle Jr. objected to Hirsch’s testimony. McGuinness claimed that Hirsch was unqualified because he is an academic and does not have experience participating in interrogations. McGuinness also argued that the testimony would be prejudicial.

Superior Court Judge Elpedio N. Vitale held a hearing to determine whether Hirsch should be allowed to testify. Hirsch cited statistics from the Innocence Project, an organization that works to exonerate the wrongly convicted. Hirsch testified that “They found that hundreds of people had been wrongly convicted and about one-quarter of them had confessed.”

Hirsch described the Reid technique, which is a commonly used police interrogation tactic. Hirsch explained that the nine-step process uses confrontation and minimalization to break suspects down. Utilizing this technique, “The suspect is told confession is the only way out and it’s not a particularly bad way out.” Hirsch said that the problem with the Reid technique is that it breaks down the innocent as well as the guilty.

Griffin’s attorneys argued that during Griffin’s 3-4 hour interrogation, the detectives lied to him about the evidence against him and told him he needed to confess. Detective David Zaweski acknowledged that he and Detective Nicole Natale lied about the evidence they had.

Griffin acknowledged that he read and signed a Miranda form advising him that he had the right to remain silent and to have an attorney present. He also admitted that the detectives told him that he could stop the questioning at any time. However, Griffin also said that he felt pressure from the detectives. “I thought I had no choice. They kept telling me I did it. I kept saying I had nothing to do with the crime.”

Judge Vitale decided that Hirsch would be allowed to testify, but only generally. Hirsch would be allowed to testify about the techniques of confrontation and minimalization, but would not be allowed to specifically discuss the interrogation of Griffin and his confession.

During his testimony in front of the jury, Hirsch explained that aggressive police questioning sometimes causes a suspect to confess to a crime they did not commit.


Jurors found Griffin guilty of murder. He will be sentenced in May.

Class Action

Trial Court Erred by Disallowing Expert’s Opinion when It Refused to Certify Class in an Unpaid Wage Lawsuit

ABM Industries provides janitorial services to businesses across the United States. Thousands of ABM employees work at hundreds of job sites in California. Some of those employees filed a class action lawsuit against ABM in a California court, alleging that the company violated California wage laws by failing to:

  • keep required records of the time worked by employees,
  • follow laws regarding compensation for meal breaks,
  • pay split-shift premiums required by California law, and
  • reimburse employees for expenses incurred when traveling between job sites.

ABM’s contracts with clients generally provide for a fixed fee in exchanged for services provided, regardless of ABM’s cost of providing those services. Accordingly, if ABM employees earn extra wages, ABM must absorb that cost. The employees alleged that ABM deliberately underpaid its employees in order to enhance its profitability.

The employees requested certification of their lawsuit as a class action. The class consisted of about 35,000 employees, divided into several subclasses according to the specific wage violations that each employee suffered.

The certification request relied in part on expert testimony that the trial court refused to consider. The employees appealed, arguing that their expert testimony was admissible.

Class Certification

Class actions consolidate individual claims into a single lawsuit. Plaintiffs benefit from class actions when they can obtain a remedy for a legal violation that they would be unable to pursue in an individual lawsuit (usually because the cost of litigation would exceed the amount of compensation the individual could expect to receive). A class action is also a more efficient way to resolve claims than multiple lawsuits raising the same issues against the same defendant.

Courts must certify a lawsuit before it can proceed as a class action. A certification decision is based on evidence that legal and factual questions common to all the class members predominate over individual differences in the claims. Class actions are often used to address wage law violations when a large employer has generally applied the same unlawful policy or practice to wage payments for employees who hold the same or similar jobs.

The ABM employees supplied the court with evidence that ABM applied a uniform policy that paid employees based on their anticipated schedules of work, not on their actual hours worked — a practice that would violate California and federal law. They alleged, for example, that ABM’s payroll system automatically deducted a 30-minute meal break each day from the hours each employee worked, without determining whether employees actually took a lunch break and despite the fact that many employees skipped lunch to finish their work within the time they were given to complete it.

Expert Evidence

The employees based their class certification motion in part on expert evidence from Aaron Woolfson, “a provider of database services who analyzed certain timekeeping and payroll data maintained by ABM with respect to its employees.” Woolfson analyzed more than a million shifts that employees worked for more than five hours (when a meal break must be provided). ABM’s records concerning those shifts failed to show evidence of the time an employee “clocked in” and “clocked out.”

In 94% of the shifts Woolfson examined, a meal break was automatically deducted from hours worked, and there was no evidence that ABM ever gave employees the required premium pay they were owed for working through lunch. His analysis also showed that few employees were reimbursed for their cost of traveling from one job site to another during a workday.

The trial court declined to consider Woolfson’s evidence. The court concluded that Woolfson was not shown to be “an expert on anything material to the class certification motion.” Because Woolfson was not an expert, he could not give opinions based on hearsay. Finally, the court decided that his opinions were inadmissible because they didn’t “prove anything” relevant to the certification issue.

The trial court rejected Woolfson as an expert because he had no “formal training or degrees that would qualify him as an expert to review the timekeeping and payroll data at issue.” The court also rejected Woolfson’s assertion that he had “provided payroll and timekeeping database analysis for attorneys in numerous wage-hour cases” because Woolfson did not provide “specific facts of the type that is usually relied upon to qualify an expert” (such as, presumably, identification of the cases in which he rendered opinions and the lawyers who hired him).

The court concluded that Woolfson’s assertion that he had “extensive experience in creating, managing, and analyzing large databases” was too general because the court did not know what Woolfson meant by “extensive” (despite Woolfson’s list of databases he had created, managed, and analyzed), and because Woolfson did not specify “how many years, how many assignments, what the nature of the assignments were, what the nature of his tasks were or anything of the like.”

The employees asked the court to reconsider, offering additional evidence of Woolfson’s expertise, including evidence that he had been accepted as an expert by other courts. The court denied the motion, ruling that Woolfson’s opinions were not relevant to the certification issue even if he was qualified to give them.

Appellate Opinion

As an initial matter, the California Court of Appeals noted that the gatekeeping role played by trial courts when they determine the admissibility of expert evidence is not a grant of unlimited discretion. Trial courts must be “cautious in excluding expert testimony” as their narrow goal is simply to exclude “clearly invalid and unreliable” expert opinions.

The trial court ruled that Woolfson’s testimony was inadmissible because he was not qualified as an expert and because his opinions, even if he was qualified to render them, were not relevant. The court of appeals disagreed with both rulings.

Woolfson’s Expertise

The appellate court noted that expertise depends on the subject of the proposed testimony. An expert’s qualifications are therefore “not subject to rigid classification according to formal education or certification.” Knowledge of, and familiarity with, the subject matter of testimony can be acquired by sufficient experience. “Once this threshold has been met, questions regarding the degree of an expert’s knowledge go more to the weight of the evidence presented than to its admissibility.”

Woolfson founded a company that develops database systems so that telecommunications companies can manage their billing. He also manages a company that provides billing and database mechanisms that allow banks to keep track of paperwork concerning mortgage loans. He has provided “extensive database management services to both government and private industries” and has extensive experience in creating, managing, and analyzing large timekeeping databases.

The court noted that “additional information regarding the specifics of Woolfson’s expertise in matters relevant to this case would clearly have been preferable,” including details about his clients, the number of years he had worked with databases, and his professional certifications — information that he later provided in the supplemental declaration that the trial court rejected. The court of appeals nevertheless concluded that the information in his initial declaration was sufficient to qualify him as an expert in database analysis.

The trial court also erred by focusing on Woolfson’s lack of a formal degree, given Woolfson’s “clear familiarity with numerous, highly complex transactions in that subject matter.” A formal education may be a prerequisite for expertise in some fields, but database analysis is not one of them.

“More is better” is the lesson to be learned by lawyers who seek to qualify a witness as an expert. Although the employees’ lawyers may have been lulled into complacency by ABM’s failure to make more than a cursory challenge to Woolfson’s expertise, this decision serves as a reminder that detailed facts establishing an expert’s qualifications should always be provided to the trial court in response to a motion asking the court to reject the admission of the expert’s opinions.

Relevance of Woolfson’s Opinion

The appellate court also rejected the trial court’s conclusion that Woolfson’s opinions were not relevant. Without parsing each separate opinion, the appellate court noted that at least some of Woolfson’s opinions, “based on his manipulation of ABM’s database,” were “clearly admissible as matters beyond the common knowledge or experience of an ordinary witness.” The court also noted that “as evidence of ABM’s common wage and timekeeping practices, Woolfson’s results would unquestionably aid a jury in its search for the truth regarding any alleged classwide wage or hour violations in this case.”

The appellate court was “mystified” by the trial court’s “wholesale rejection” of Woolfson’s opinions. The court expressed concern that “the trial court’s conclusions regarding the admissibility of the Woolfson materials were impermissibly tainted by its strong views with respect to the underlying merits of plaintiffs’ class certification motion,” a determination that was based “on the mistaken notion that database analysis of timekeeping and payroll records cannot be used as a means to show common practices for purposes of class certification.”

The trial court should instead have accepted Woolfson’s opinions as evidence of ABM’s payroll practices that were common to all similarly situated employees, and then weighed those opinions against evidence of the need for individualized determinations that might preclude class certification. The trial court therefore erred in failure to consider Woolfson’s expert opinions.