Comparison of Frye and Daubert Rules

June 1, 2013

Saturday, June 1, 2013

Several people have asked me to explain the Daubert rule and compare it to the Frye rule. Today is a good opportunity to do that since we are experiencing a bit of calm before the storm.

Judge Nelson scheduled a Frye hearing for June 6 and 7 to determine whether to permit the State to present expert testimony identifying voices in the background of a 911 call. The purpose of a Frye hearing is to determine whether to admit evidence derived from a new or novel scientific theory or methodology. In Frye v. United States, 293 F. 1013 (D.C. Cir. 1923), the Court held that such evidence should be excluded unless the new or novel scientific theory or methodology is generally accepted in the relevant scientific community.

I previously wrote about the Frye rule here. Basically, it is a counting heads test that does not require the trial judge to understand the new or novel scientific theory or methodology.

The disadvantage of the Frye rule is that it may result in the exclusion of results obtained with theories and methodologies that are capable of producing accurate and reliable results, but are too new to have passed the test of peer review and become generally accepted in the relevant scientific community.

This hole in the Frye rule eventually led to the SCOTUS adopting a new rule in Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579 (1993). Significant changes in long existing legal rules generally require compelling facts, particularly if the rule change is going to cost corporate America big money. Daubert was such a case.

Writing for the majority, Justice Blackmun described that set of facts at pp. 582-583:

Petitioners Jason Daubert and Eric Schuller are minor children born with serious birth defects. They and their parents sued respondent in California state court, alleging that the birth defects had been caused by the mothers’ ingestion of Bendectin, a prescription antinausea drug marketed by respondent. Respondent removed the suits to federal court on diversity grounds.

After extensive discovery, respondent moved for summary judgment, contending that Bendectin does not cause birth defects in humans and that petitioners would be unable to come forward with any admissible evidence that it does. In support of its motion, respondent submitted an affidavit of Steven H. Lamm, physician and epidemiologist, who is a well-credentialed expert on the risks from exposure to various chemical substances. Doctor Lamm stated that he had reviewed all the literature on Bendectin and human birth defects—more than 30 published studies involving over 130,000 patients. No study had found Bendectin to be a human teratogen (i. e., a substance capable of causing malformations in fetuses). On the basis of this review, Doctor Lamm concluded that maternal use of Bendectin during the first trimester of pregnancy has not been shown to be a risk factor for human birth defects.

Petitioners did not (and do not) contest this characterization of the published record regarding Bendectin. Instead, they responded to respondent’s motion with the testimony of eight experts of their own, each of whom also possessed impressive credentials. These experts had concluded that Bendectin can cause birth defects. Their conclusions were based upon “in vitro” (test tube) and “in vivo” (live) animal studies that found a link between Bendectin and malformations; pharmacological studies of the chemical structure of Bendectin that purported to show similarities between the structure of the drug and that of other substances known to cause birth defects; and the “reanalysis” of previously published epidemiological (human statistical) studies.

The Court held that Rule 702 of the Federal Rules of Evidence replaced the Frye Rule. Rule 702 states:

If scientific, technical, or other specialized knowledge will assist the trier of fact to understand the evidence or to determine a fact in issue a witness qualified as an expert by knowledge, skill, experience, training, or education, may testify thereto in the form of an opinion or otherwise, if

(1) the testimony is based on upon sufficient facts or data,

(2) the testimony is the product of reliable priniciples and methods, and

(3) the witness has applied the principles and methods reliably to the facts of the case.

[Note that the language beginning with “or otherwise, if” was added to the rule in 2000 after the SCOTUS decided Daubert]

Application of Rule 702 must involve a consideration of the following factors discussed at pp. 592-595:

Faced with a proffer of expert scientific testimony, then, the trial judge must determine at the outset, pursuant to Rule 104(a), whether the expert is proposing to testify to (1) scientific knowledge that (2) will assist the trier of fact to understand or determine a fact in issue. This entails a preliminary assessment of whether the reasoning or methodology underlying the testimony is scientifically valid and of whether that reasoning or methodology properly can be applied to the facts in issue. We are confident that federal judges possess the capacity to undertake this review. Many factors will bear on the inquiry, and we do not presume to set out a definitive checklist or test. But some general observations are appropriate.

[Note that the previous paragraph changes the trial court’s job from counting heads to functioning as a gatekeeper]

Ordinarily, a key question to be answered in determining whether a theory or technique is scientific knowledge that will assist the trier of fact will be whether it can be (and has been) tested. “Scientific methodology today is based on generating hypotheses and testing them to see if they can be falsified; indeed, this methodology is what distinguishes science from other fields of human inquiry.” Green 645. See also C. Hempel, Philosophy of Natural Science 49 (1966) (“[T]he statements constituting a scientific explanation must be capable of empirical test”); K. Popper, Conjectures and Refutations: The Growth of Scientific Knowledge 37 (5th ed. 1989) (“[T]he criterion of the scientific status of a theory is its falsifiability, or refutability, or testability”) (emphasis deleted).

Another pertinent consideration is whether the theory or technique has been subjected to peer review and publication. Publication (which is but one element of peer review) is not a sine qua non of admissibility; it does not necessarily correlate with reliability, see S. Jasanoff, The Fifth Branch: Science Advisors as Policymakers 61-76 (1990), and in some instances well-grounded but innovative theories will not have been published, see Horrobin, The Philosophical Basis of Peer Review and the Suppression of Innovation, 263 JAMA 1438 (1990). Some propositions, moreover, are too particular, too new, or of too limited interest to be published. But submission to the scrutiny of the scientific community is a component of “good science,” in part because it increases the likelihood that substantive flaws in methodology will be detected. See J. Ziman, Reliable Knowledge: An Exploration of the Grounds for Belief in Science 130-133 (1978); Relman & Angell, How Good Is Peer Review?, 321 New Eng. J. Med. 827 (1989). The fact of publication (or lack thereof) in a peer reviewed journal thus will be a relevant, though not dispositive, consideration in assessing the scientific validity of a particular technique or methodology on which an opinion is premised.

Additionally, in the case of a particular scientific technique, the court ordinarily should consider the known or potential rate of error, see, e. g., United States v. Smith, 869 F. 2d 348, 353-354 (CA7 1989) (surveying studies of the error rate of spectrographic voice identification technique), and the existence and maintenance of standards controlling the technique’s operation, see United States v. Williams, 583 F. 2d 1194, 1198 (CA2 1978) (noting professional organization’s standard governing spectrographic analysis), cert. denied, 439 U. S. 1117 (1979).

Finally, “general acceptance” can yet have a bearing on the inquiry. A “reliability assessment does not require, although it does permit, explicit identification of a relevant scientific community and an express determination of a particular degree of acceptance within that community.” United States v. Downing, 753 F. 2d, at 1238. See also 3 Weinstein & Berger ¶ 702[03], pp. 702-41 to 702-42. Widespread acceptance can be an important factor in ruling particular evidence admissible, and “a known technique which has been able to attract only minimal support within the community,” Downing, 753 F. 2d, at 1238, may properly be viewed with skepticism.

The inquiry envisioned by Rule 702 is, we emphasize, a flexible one. Its overarching subject is the scientific validity—and thus the evidentiary relevance and reliability—of the principles that underlie a proposed submission. The focus, of course, must be solely on principles and methodology, not on the conclusions that they generate.

And there you have it.

Zimmerman: Pssst hey buddy what’s a Frye hearing

May 7, 2013

Tuesday, May 7, 2013

To Frye or not to Frye,
that is the question.
Whether ’tis nobler in the mind
to suffer the slings and arrows
of outrageous fortune
or to take arms against
a sea of troubles
and by opposing end them.

Hamlet, Act III, by William Shakespeare

Good morning:

I write today to explain the Frye Rule and Mark O’Mara’s latest strategic mistake. Let’s begin with the mistake.

If Judge Nelson grants his motion, there will not be any testimony by an expert witness regarding the identity of the person who uttered the terrified shriek. That will not help the defense because that intense, high-pitched, and prolonged nightmarish shriek of sheer terror ends abruptly with the fatal gunshot to the heart.

Just as it does not take a weatherman to tell which direction the wind blows, no juror is going to have any difficulty figuring out that the person who uttered that inhuman shriek is the victim of that gunshot. No juror is going to believe that the person armed with the gun; who pulled it out of a holster; who extended his arm; who aimed the gun taking care to make sure his left hand was out of the way; and who pulled the trigger at point-blank range is the person who screamed.

I am certain the prosecutor will not forget to remind the jury that the defendant told the police that he kept screaming for help after the shot because he thought he missed Trayvon Martin.

Apparently, Mark O’Mara has not listened to that agonizing shriek because, if he had listened to it, he never would have filed this ridiculous motion that can only hurt his client, if Judge Nelson grants it, since the absence of expert testimony would simplify identifying Trayvon as the source of the shriek while also disproving the defendant’s claim that Trayvon was beating him to death and attempting to smother him when he fired the fatal shot.

Breath. Taking. Stupidity.

Now, let’s take a look at the Frye-hearing request.

Every once in awhile someone develops a new theory or a new way of performing some task (i.e., a new methodology). A lawyer finds out about it and decides he wants to apply that new theory or methodology to win a case. Opposing counsel says, “Not so fast, pal. Not without a Frye hearing.”

A Frye hearing is a pretrial hearing to determine if evidence obtained pursuant to a new theory or methodology should be admitted or excluded during the trial. Think of it as a judicial screening device to exclude potentially inaccurate and unreliable evidence based on a new untested theory or methodology.

We call it a Frye hearing because the first published case that dealt with this issue was Frye v. United States, 293 F. 1013 (D.C. Cir 1923). Judge Van Orsdell laid out the facts:

A single assignment of error is presented for our consideration. In the course of the trial counsel for defendant offered an expert witness to testify to the result of a deception test made upon defendant. The test is described as the systolic blood pressure deception test. It is asserted that blood pressure is influenced by change in the emotions of the witness, and that the systolic blood pressure rises are brought about by nervous impulses sent to the sympathetic branch of the autonomic nervous system. Scientific experiments, it is claimed, have demonstrated that fear, rage, and pain always produce a rise of systolic blood pressure, and that conscious deception or falsehood, concealment of facts, or guilt of crime, accompanied by fear of detection when the person is under examination, raises the systolic blood pressure in a curve, which corresponds exactly to the struggle going on in the subject’s mind, between fear and attempted control of that fear, as the examination touches the vital points in respect of which he is attempting to deceive the examiner.

In other words, the theory seems to be that truth is spontaneous, and comes without conscious effort, while the utterance of a falsehood requires a conscious effort, which is reflected in the blood pressure. The rise thus produced is easily detected and distinguished from the rise produced by mere fear of the examination itself. In the former instance, the pressure rises higher than in the latter, and is more pronounced as the examination proceeds, while in the latter case, if the subject is telling the truth, the pressure registers highest at the beginning of the examination, and gradually diminishes as the examination proceeds.

Prior to the trial defendant was subjected to this deception test, and counsel offered the scientist who conducted the test as an expert to testify to the results obtained. The offer was objected to by counsel for the government, and the court sustained the objection. Counsel for defendant then offered to have the proffered witness conduct a test in the presence of the jury. This also was denied.

Judge Van Orsdell then proceeded to define the new rule:

The rule is that the opinions of experts or skilled witnesses are admissible in evidence in those cases in which the matter of inquiry is such that inexperienced persons are unlikely to prove capable of forming a correct judgment upon it, for the reason that the subject-matter so far partakes of a science, art, or trade as to require a previous habit or experience or study in it, in order to acquire a knowledge of it. When the question involved does not lie within the range of common experience or common knowledge, but requires special experience or special knowledge, then the opinions of witnesses skilled in that particular science, art, or trade to which the question relates are admissible in evidence.

Numerous cases are cited in support of this rule. Just when a scientific principle or discovery crosses the line between the experimental and demonstrable stages is difficult to define. Somewhere in this twilight zone the evidential force of the principle must be recognized, and while courts will go a long way in admitting expert testimony deduced from a well-recognized scientific principle or discovery, the thing from which the deduction is made must be sufficiently established to have gained general acceptance in the particular field in which it belongs.

We think the systolic blood pressure deception test has not yet gained such standing and scientific recognition among physiological and psychological authorities as would justify the courts in admitting expert testimony deduced from the discovery, development, and experiments thus far made.

(Emphasis supplied)

The issue Judge Nelson would have to decide, assuming she decides to hold a Frye hearing, is whether the methodologies used by the state’s experts are generally accepted by audiologists as capable of producing accurate and reliable results.

The Frye test has been described as a counting-heads test because it does not require the judge to understand the theory or methodology at issue. The judge need only count the heads of the experts in the particular field and decide whether they generally accept the methodology.

As I recall, two experts used different methodologies to compare the shriek to a voice exemplar provided by the defendant. One methodology has been used for many years and the other one, which was developed recently, involves the use of a software program.

Both experts have excluded the defendant as the source of the scream.

Since the first method has been used for many years, it probably has survived a Frye challenge in Florida.

The second method may be too new to have been challenged at a Frye hearing.

The glaring, and I believe fatal, omission in O’Mara’s motion for a Frye hearing is the absence of any supporting affidavits from experts in audiology that one or both of the methodologies used are not generally accepted by audiologists as capable of producing accurate and reliable results.

Nobody gives a damn about what the non-expert lawyer thinks. He is not qualified to express an opinion about general acceptance of these methodologies.

Therefore, I would deny his motion for a Frye hearing.

Notice that regardless whether Judge Nelson grants or denies O’Mara’s motion, the State will still be required to lay a proper foundation for each of its expert audiologists at trial pursuant to Evidence Rule 702 that the witness is a duly qualified expert in the field and the result obtained using the particular methodology in question will assist the jury to decide who is screaming.

In conclusion, if I were the prosecutor, I would be inclined to try the case without putting on any audiologists during my case-in-chief for the simple reason that I do not believe they are necessary. This is another illustration of the KISS rule.

BTW, all that sparring about whether Tracy Martin could identify Trayvon as the source of the shriek does not matter.

Hardly anyone ever shrieks like that and lives to tell about it, so it stands to reason that no one, including his father, ever heard Trayvon utter a shriek like that. This may explain why it may not be possible for any expert to positively identify the source of the shriek without considering the circumstances or context that produced it.

That’s why it sounds inhuman.


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Opinion Evidence, Expert Witnesses, And The Plight Of The Injured Plaintiff

January 9, 2012

Junk science and the charlatans for sale who rely on it while masquerading as objective experts above the fray of litigation constitute a serious and continuing problem to the fair administration of justice in our legal system.

The Federal Rules of Evidence (FRE) distinguish between ordinary witnesses and expert witnesses. With a few exceptions, such as whether a person appeared to be intoxicated or how fast someone was driving, ordinary witnesses are supposed to restrict their testimony to facts they perceive through their five senses. Experts are permitted to express opinions that are typically expressed to a “reasonable scientific (or medical) certainty.” A major part of the problem for indigent and poor plaintiffs is lack of sufficient funds to hire sufficiently qualified experts. Plaintiffs personal injury lawyers usually advance the costs of such witnesses and reimburse themselves out of a favorable money judgment. In practice, this means that they will not agree to take a case unless they are virtually certain they will win. It also means that the lawyer or firm that takes the case must have a big war chest and there are not very many who do. Meanwhile, corporations and insurance companies have virtually unlimited funds available to retain multiple experts and they routinely subject plaintiffs to delays and hurdles to leap until money runs out and they settle the case for less than it is worth or they drop out.

Fortunately, in criminal cases, an indigent defendant has a Sixth Amendment right to have the court appoint and compensate an expert when an expert’s assistance is “reasonably necessary” to present a defense. Ake v. Oklahoma, 470 U.S. 68 (1985).

There are any number of urban legends about undeserving plaintiffs who won multiple million dollar judgments against ‘poor’ corporations and insurance companies, but I doubt that any of the stories are true. Even if some of them are true, they pale when considering the following studies.

When considering whether there should be limits on tort liability for damages due to personal injury, keep in mind that, according to HealthGrades’ fifth annual Patient Safety in American Hospitals Study, patient safety incidents cost the federal Medicare program $8.8 billion and resulted in 238,337 potentially preventable deaths during 2004 through 2006.

This study followed HealthGrades’ studies in 2000-2002 that reported 195,000 preventable deaths per year in U.S. hospitals.

Here are the applicable rules regarding ordinary and expert witness testimony.

As you read the rules and my discussion of Daubert v. Merrell Dow Pharmaceuticals that follows, keep in mind that one of the many evidence-based debates that we should be having as an educated democratic society, but tragically are not having, is what should we do to reform these rules and other practices to assure fair and equitable results to economically disadvantaged people who suffer personal injury.

Rule 701 provides:

If the witness is not testifying as an expert, the witness’ testimony in the form of opinions or inferences is limited to those opinions or inferences which are

(a) rationally based on the perception of the witness,

(b) helpful to a clear understanding of the witness’ testimony or the determination of a fact in issue, and

(c) not based on scientific, technical, other specialized knowledge within the scope of Rule 702.

Rule 702 provides:

If scientific, technical, or other specialized knowledge will assist the trier of fact to understand the evidence or to determine a fact in issue, a witness qualified as an expert by knowledge, skill, experience, training, or education, may testify thereto in the form of an opinion, or otherwise, if

(1) the testimony is based upon sufficient facts or data,

(2) the testimony is the product of reliable principles and methods, and

(3) the witness has applied the principles and methods reliably to the facts of the case.

In Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579 (1993), the United States Supreme Court reversed the Ninth Circuit Court of Appeals decision affirming the trial court’s dismissal of the plaintiffs’ lawsuit against Merrell Dow Pharmaceuticals for birth defects allegedly caused by Bendectin, a drug manufactured by Merrell Dow to prevent pregnant women from suffering morning sickness. The plaintiffs had relied on in vitro and in vivo animal studies, pharmacological studies, and reanalysis of other published studies to show that Bendectin could have caused the birth defects. Nevertheless, trial court had dismissed their lawsuit based on the Frye Rule, which prohibits the use of evidence that has been obtained from using a scientific methodology or process that has not been generally accepted in the scientific community.

The United States Supreme Court rejected the Frye Rule in Daubert as unnecessarily restrictive of new discoveries in science because it amounted to little more than counting heads in the scientific community to determine if a principle or methodology was generally accepted rather than evaluating the merits of the new principle or methodology. Therefore, even though the scientific community had not yet generally accepted that Bendectin caused birth defects, the Court concluded that the studies relied on by the plaintiffs were sufficient such that they should have been been permitted to present them to a jury to consider.

In Daubert the Court basically appointed trial judges to function as gatekeepers in determining whether to admit evidence based on novel scientific principles or methodologies. The Court set forth a non-exclusive checklist for trial judges to apply in assessing the reliability of scientific evidence. The specific factors the Court mentioned are:

(1) whether the expert’s technique or theory can be or has been tested according to some objective process,

(2) whether the technique or theory has been subjected to peer review and publication,

(3) whether there was a known or potential rate of error for the technique or theory and, if so, whether it was applied,

(4) whether applicable laboratory standards and controls were used, and

(5) whether the technique or theory used has been generally accepted in the scientific community (which is the Frye Rule downgraded from an outcome-determinative rule to one of several factors that should be considered).

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