Legal Definitions - Frye standard

The Frye standard is a legal rule used by some courts to decide whether scientific evidence or expert testimony is reliable enough to be presented to a jury. It originated from the 1923 case of Frye v. United States.

Under the Frye standard, for scientific evidence or an expert's opinion to be admissible in court, the scientific method, theory, or technique upon which it is based must be "generally accepted" by the relevant scientific community. This means that the approach must be widely recognized and endorsed by experts in that particular field, rather than being a novel or unproven concept.

While many states and federal courts have moved to a more flexible standard (the Daubert standard), the Frye standard is still applied in some jurisdictions. It is often seen as a high bar for new scientific advancements, as it prioritizes widespread acceptance over other factors like rigorous testing or peer review.

Here are some examples illustrating how the Frye standard might be applied:

• Scenario 1: A new forensic DNA analysis technique.

  Imagine a prosecutor wants to introduce evidence from a brand-new method of DNA analysis that can extract genetic material from extremely degraded samples, even those previously thought impossible to test. This technique has only been developed by a single research lab and published in one scientific journal, but it has not yet been widely adopted, replicated by other labs, or endorsed by major forensic science organizations.

  How it illustrates the Frye standard: A court applying the Frye standard would likely exclude this evidence. Even if the new technique shows promise, it has not achieved "general acceptance" within the broader forensic science community. The standard requires that the methodology be widely recognized and trusted by experts in the field before it can be used in court.

• Scenario 2: Expert testimony based on a novel psychological assessment.

  In a child custody case, a psychologist proposes to testify about a parent's fitness using a newly developed psychological assessment tool. This tool claims to predict parenting capacity with high accuracy based on a unique set of behavioral indicators. However, the assessment has not undergone extensive peer review, is not taught in standard psychology programs, and is not commonly used or recognized by the American Psychological Association or similar professional bodies.

  How it illustrates the Frye standard: A judge operating under the Frye standard would probably disallow the psychologist's testimony if it relies solely on this novel assessment. The methodology behind the assessment lacks the "general acceptance" required from the broader psychological community, meaning it hasn't been sufficiently vetted and embraced by specialists in that field.

• Scenario 3: Evidence from an experimental medical diagnostic device.

  A plaintiff in a personal injury lawsuit seeks to introduce medical evidence of a specific injury diagnosed using an experimental device that measures subtle energy fields in the body. This device is only used by a small group of practitioners who subscribe to alternative medicine theories, and its underlying scientific principles are not recognized or accepted by mainstream medical organizations or the vast majority of medical doctors.

  How it illustrates the Frye standard: Under the Frye standard, the court would almost certainly reject the evidence derived from this device. The scientific basis and methodology of the device are not "generally accepted" by the conventional medical community. The Frye standard ensures that only scientific evidence that has achieved broad consensus and acceptance among relevant experts is presented in a courtroom.