Tag Archives: Frye

Expert Testimony May Be Necessary to Counter ShotSpotter Evidence

The latest technology to capture the attention of law enforcement is called ShotSpotter. The manufacturer claims that hidden microphones installed in neighborhoods can tell the difference between gunshots and other loud noises. Rather than waiting for someone to report a shooting, police agencies that rely on the technology dispatch officers to the location where the shots were allegedly fired.

The technology has generated criticism. Apart from concerns about the concentration of microphones in black neighborhoods, the Electronic Frontier Foundation is worried that police agencies might use the microphones to eavesdrop on private conversations. Whether the ShotSpotter system reduces gun violence seems doubtful. 

From the standpoint of an expert witness blog, the question is whether defense attorneys should use expert witnesses to challenge ShotSpotter evidence in court. There is good reason to think that Daubert challenges should be filed, and experts employed, whenever ShotSpotter evidence is a critical component of the prosecution’s proof.

Investigations of ShotSpotter 

A recent investigation calls into question the evidentiary value of ShotSpotter reports. Last year, Michael Williams brought a shooting victim to a Chicago hospital. Williams said the victim was shot during a drive-by shooting. After the victim died, the police arrested Williams for the victim’s murder. Why Williams would bring the victim to a hospital if Williams intended to kill him is a question that raises serious doubt about Williams’ guilt.

The police built their case on video and ShotSpotter evidence. The video evidence showed only that Williams’ car had stopped in the 6300 block of South Stony Island Avenue at 11:46 p.m. on the night of the shooting. The police contended that the victim was shot at that location. No video evidence supports that contention.

The police contend that they received a “shots fired” alert from ShotSpotter at the Stoney Island location. In fact, company records show that “19 ShotSpotter sensors detected a percussive sound at 11:46 p.m. and determined the location to be 5700 South Lake Shore Drive—a mile away from the site where prosecutors say Williams committed the murder.” The company’s algorithms identified the sound as an exploding firework.

Company records show that “a ShotSpotter analyst manually overrode the algorithms and ‘reclassified’ the sound as a gunshot.” Months later, a different ShotSpotter employee manually changed the alert’s coordinates to a South Stony Island Drive location near the place where Williams’ car can be seen on camera.

The evidence suggests that ShotSpotter changed its data to support the theory that Williams shot the victim. Williams’ lawyer filed a motion that challenged the ShotSpotter evidence, arguing that it failed to meet the Illinois standard for the admissibility of expert opinions. Rather than defending against the motion, prosecutors agreed not to use ShotSpotter evidence against Williams. 

Daubert Challenges to ShotSpotter Evidence

The investigation suggests that the Chicago incident was not an isolated example of ShotSpotter tailoring its conclusions to match law enforcement theories. In a carefully worded statement, ShotSpotter denied that it has ever “altered the information in a court-admissible detailed forensic report based on fitting a police narrative.” The statement claims that ShotSpotter is “100{d61575bddc780c1d4ab39ab904bf25755f3b8d1434703a303cf443ba00f43fa4} accurate,” a claim of certainty that many reputable forensic science experts condemn. The statement asserts that ShotSpotter has been admitted over ten Frye challenges and one Daubert challenge, but it does not state how many challenges to admissibility have succeeded.

ShotSpotter commissioned a report by CSG Analysis, a “police officer-owned and operated company,” that is filled with unsurprising praise of ShotSpotter. The report does not purport to be based on a scientific analysis. Rather, it is based on interviews with police officers in cities that have paid to install ShotSpotter. 

Despite the report’s obvious credibility issues, the authors acknowledge that false positives — sounds that could be caused by trucks, dumpsters, construction, church bells, and all the other sources of concussive sound — are a significant operational problem with ShotSpotter. In two of the seven jurisdictions where interviews were conducted, half of the ShotSpotter alerts were believed to be false positives. A recent study found that Chicago police officers investigated 40,000 ShotSpotter alerts in a 21-month period that resulted in no evidence that shots had been fired.

Challenges to ShotSpotter Evidence

ShotSpotter claims that its analysts can identify actual gunshots when evidence is needed for court. The analysts allegedly perform a deeper dive into the data than the system’s algorithms perform. ShotSpotter contends that a more reliable human analysis explains why results are changed after police agencies contact ShotSpotter. Since one purpose of algorithms is to eliminate human bias, one might wonder whether second-guessing algorithms calls either the algorithms or the analyst’s opinions into question.

The admissibility of ShotSpotter evidence, whether generated by algorithms or humans, is not a foregone conclusion. A Daubert challenge should focus on whether ShotSpotter results been accepted by any independent scientific community, whether its analytical system has been peer reviewed, whether it has a known error rate, and whether conclusions drawn by analysts have been verified by independent testing. The National Juvenile Defender Center has compiled materials, including transcripts of testimony that ShotSpotter witnesses have given at Daubert/Frye hearings, that may guide those challenges.

Notably, a California appellate court reversed a conviction based on ShotSpotter evidence because the trial court did not hold a pretrial hearing to determine whether the evidence was reliable. The court noted the dearth of appellate opinions considering the admissibility of ShotSpotter evidence and concluded that courts could not assume the reliability of the novel technology.

ShotSpotter offers to supply prosecutors with expert witnesses who will testify in court for $350 an hour with a two-hour minimum. Retaining a defense expert with a background in acoustic science may be critical to countering those experts and to bringing a successful Daubert challenge. 

Meade and Prettyman Courthouse

D.C. Court of Appeals Adopts Daubert

The court that first adopted the Frye standard of expert witness admissibility has formally jettisoned that standard in favor of the Daubert standard. The D.C. Court of Appeals has now joined the federal courts and the majority of states in accepting Daubert as the standard under which the admissibility of expert testimony should be evaluated.

Evidence in the D.C. Court System

The District of Columbia Court of Appeals, like the District itself, is an oddity in American law. The District falls under federal jurisdiction but in most respects it operates as a state. An elected D.C. Council has the power to pass laws, but the laws are subject to the approval of Congress. The District’s trial courts, although operated by the federal government, are separate from the federal courts that decide federal cases. Trial court decisions in the District are appealed to the D.C. Court of Appeals, which describes itself as “the equivalent of a state supreme court.”

The District has not codified its own rules of evidence. Courts in the District are not bound by the Federal Rules of Evidence, although they often turn to the federal rules for guidance. In many instances, the D.C. Court of Appeals has adopted the federal rule, although sometimes in modified form to retain elements of common law rules it has historically followed.

The Competing Standards of Frye and Daubert

The Frye standard for the admission of expert testimony asks whether the expert’s opinion was based on principles that had been generally accepted within the relevant scientific community. The Frye standard was created by the D.C. Court of Appeals in Frye v. United States, a case it decided in 1923. Most states adopted the Frye standard in the years that followed.

State court reliance on the Frye standard changed dramatically after the United State Supreme Court decided Daubert v. Merrell Dow Pharmaceuticals. The Daubert decision interpreted Rule 702 of the Federal Rules of Evidence to require a broader test for expert evidence admissibility than Frye imposed. Under Daubert, judges ask whether the expert’s opinion is based on sufficient facts or data, whether the proposed evidence is based on a reliable methodology, and whether the expert has reliably applied the methodology to the facts.

Unlike the Frye standard, the Daubert standard does not require expert opinions to be based on theories that have gained widespread acceptance, provided that the expert applied a reasonable methodology in a reasonable way to facts that are sufficient to allow the expert to form an opinion. In that sense, Daubert broadened the universe of admissible expert evidence, although many of its proponents praise it for narrowing the range of “junk science” and other unreliable expert evidence that can be admitted in a trial.

Motorola v. Murray

All of the judges on the D.C. Court of Appeals participated in the court’s decision in Motorola v. Murray. The case involved a claim that long-term exposure to cell-phone radiation causes brain tumors. After weeks of pretrial hearings, the trial judge decided that most of the testimony offered by the plaintiffs’ experts would be admissible under the existing Frye standard, but most would be inadmissible under a Daubert standard.

According to the trial judge, the different results were attributable to court decisions that limited the Frye inquiry to whether an expert’s methodology was generally accepted and thus presumptively reliable. Unlike Daubert, the Frye standard did not allow courts to ask whether the expert applied the methodology in a reliable way. Under Frye, that question was for the jury to decide.

D.C. Abandons Frye Standard

In Motorola, the D.C. Court of Appeals recognized that the Daubert standard “in some respects relaxed traditional barriers to opinion testimony.” Opinions that are based on the reliable application of a reliable methodology to sufficient data are admissible even if the methodology has not been generally accepted. At the same time, the Daubert standard, unlike Frye, examines the expert’s application of the methodology. Under both Daubert and Frye, whether the expert’s conclusions are correct is for the jury to decide — but only if the judge allows the expert to testify.

The court recognized that Frye has been criticized for being “antiquated and out-of-step with modern science.” At the same time, the court noted that Daubert has been faulted “for producing inconsistent results, for making unqualified judges evaluate the work of scientists, and for invading the province of the jury.”

The court decided to adopt Daubert in both civil and criminal cases because it believed that Daubert, despite its flaws, will lead to “better decision-making by juries and trial judges alike.” Noting that the transition from Frye to Daubert will be difficult and that decisions in individual cases will probably be inconsistent, the court expressed confidence that trial courts would be guided by decisions of other jurisdictions that have adopted the widely-used Daubert standard. Finding definitive guidance might be challenging, however, given that appellate courts often disagree about the proper scope of a judge’s gatekeeping role under Daubert.

The court also cautioned that Daubert requires “a delicate touch” if judges are to avoid substituting their own judgment for conclusions that a jury should draw. The judge’s role as a gatekeeper is meant to prevent unsound evidence from reaching the jury. It is not meant to be a replacement for the adversary system of justice. The court noted that reliable applications of reliable methodologies can produce conflicting opinions, and emphasized that judges must take care not to evaluate the expert opinion itself. Only a jury can decide whether an opinion is credible.

Concurring Opinion Cites Doubtful Forensic Evidence

Judge Easterly’s notable concurring opinion urged judges applying Daubert to give special scrutiny to the opinions of forensic experts, even if the judges have grown used to admitting expert forensic opinions routinely under Frye. Judge Easterly called attention to expert methodologies that have been justly criticized as causing wrongful convictions. In particular, Judge Easterly called on trial court judges to pay special attention to the PCAST report and its recommendations for applying Daubert to dubious scientific methodologies that contribute to unreliable criminal convictions.

Photo Credit: Meade and Prettyman Courthouse, by AgnosticPreachersKid, CC BY-SA 3.0.

Florida’s Third Circuit Issues First In-Depth Treatment of Daubert

A recent decision from Florida’s Third District Court of Appeal provided an in-depth discussion on the differences between the old Frye standard of expert witness admissibility and the currently used Daubert test. In Perez v Bell South, the Court considered expert witness testimony in a personal injury claim, and clarified for future litigants how the Daubert requirements differed from the state’s previous Frye test. Although the decision applies only to Florida, analyzing the case is useful to attorneys who need to be aware how Daubert expert witness admissibility rules compare to the older standard.

Perez v Bell South Emphasizes Use of Daubert

Maria Perez filed a personal injury claim on behalf of her developmentally disabled son, Osmany, against her former employer for negligently creating a stressful work environment that resulted Osmany being born 20 weeks early. Ms. Perez alleged that Bell South caused her such significant difficulty that she suffered a placental abruption, which led to Osmany’s premature birth and subsequent developmental deficits. As part of her case, Maria called upon the medical expert testimony of Dr. Isidro Cardella, a board-certified obstetrician and gynecologist. Dr. Cardella testified that, in his opinion, Bell South’s refusal to allow Ms. Perez frequent bathroom breaks or limit her working hours to 40 created such stress on her body that she suffered the placental abruption.

The trial court dismissed Dr. Cardella’s expert testimony and Ms. Perez’s case because it was based solely on his opinion as a medical expert. Applying the Frye test, the trial judge determined that an opinion not supported by medical evidence or research is inadmissible.  Ms. Perez appealed, arguing that “pure opinion” testimony does not fall within the guidelines of Frye. On appeal, Florida’s Third District Court correctly made the dispute over Dr. Cardella’s testimony moot by analyzing under the state’s newly adopted Daubert standard – clarifying for attorneys, and judges, how expert witness testimony, including opinion, is to be evaluated in the future.

Daubert Test v Frye Test

Created by the 1993 Supreme Court decision in Daubert v Merrell Dow Pharmaceuticals, the Daubert standard sets forth an evidentiary rule that determines whether or not expert witnesses are permitted to testify at trial. Over the last two decades, all federal jurisdictions and over half of the states have implemented the Daubert test, however, a number of states, including California and Illinois, have yet to make the switch. Relevant to the Perez case, Florida’s legislature enacted a law that made the Daubert standard the official state rule as of July 2013.

Prior to Daubert, courts analyzed expert witness testimony under a test established in the 1923 case, Frye v United States. The Frye test simply required courts to determine if an expert witnesses testimony was based on scientific methods that are “sufficiently established” in, and generally accepted by, the scientific community to which the expert belongs. As the Perez Court pointed out, the Daubert standard, as adopted by Florida’s legislature in 2013, requires additional analysis. Ensuring that an expert’s methods are accepted and established by the greater scientific community is one of many factors that a court must consider under Daubert, as now codified in Florida’s rules of evidence.

Florida courts must consider a number of factors to ensure expert witness testimony is scientifically reliable – most notably determined by analyzing an expert’s methodology and scientific knowledge. In addition to an expert’s approach being generally accepted, courts must also consider the level of peer review it has been subjected to, the error rate that can influence his results, and the existence of professional standards that govern the operation of an expert’s investigation. The Daubert standard requires courts to look at a variety of factors, and the Perez case noted that a simple Frye evaluation of expert witness testimony is no longer sufficient in Florida.

Understanding the Daubert Standard

Reviewing Dr. Cardella’s testimony through a Daubert lens, Florida’s Third District Court of Appeal arrived at the same conclusion – his testimony was inadmissible. The pathway to the correct decision is important, however, because, as Ms. Perez’s attorneys pointed out, a Frye analysis is not sufficient to evaluate a pure opinion testimony. Using the Daubert test, which applies to any expert witness testimony, Florida courts can determine the admissibility of an expert’s analysis of facts and his opinion of the case. Under Daubert, Dr. Cardella’s testimony still fell short because he did not back his conclusions with scientifically reliable support.

Attorneys who intend to use expert witnesses must understand the proper application of the Daubert standard and be prepared to use an expert who can provide reliable, scientific knowledge to support testimony. With limited exception, the Daubert standard controls expert witness admissibility, and, as Florida’s Perez v Bell South demonstrates, Daubert is more comprehensive and thorough than the once widely-used Frye test.