The Frye standard, Frye test, or general acceptance test is a test used in United States courts to determine the admissibility of scientific evidence. It provides that expert opinion based on a scientific technique is admissible only when the technique is generally accepted as reliable in the relevant scientific community. In Daubert v. Merrell Dow Pharmaceuticals, 509 U.S. 579 (1993), the United States Supreme Court held that the Federal Rules of Evidence superseded Frye as the standard for admissibility of expert evidence in federal courts. Some states, however, still adhere to the Frye standard.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 the courts will go a long way in admitting experimental 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. (Emphasis added.) The Frye standard, Frye test, or general acceptance test is a test used in United States courts to determine the admissibility of scientific evidence. It provides that expert opinion based on a scientific technique is admissible only when the technique is generally accepted as reliable in the relevant scientific community. In Daubert v. Merrell Dow Pharmaceuticals, 509 U.S. 579 (1993), the United States Supreme Court held that the Federal Rules of Evidence superseded Frye as the standard for admissibility of expert evidence in federal courts. Some states, however, still adhere to the Frye standard. This standard comes from Frye v. United States, 293 F. 1013 (D.C. Cir. 1923), a case discussing the admissibility of systolic blood pressure deception test as evidence. The Court in Frye held that expert testimony must be based on scientific methods that are sufficiently established and accepted. The court wrote: In many but not all jurisdictions, the Frye standard has been superseded by the Daubert standard. States still following Frye include: California, Illinois, Maryland, Minnesota, New Jersey, New York, Pennsylvania, and Washington. On May 23, 2019, the Florida Supreme Court accepted the Daubert standard.