In the 1997 case General Electric Company, et al. v. Robert K. Joiner et ux., the U.S Supreme Court ruled that a trial court's decision to admit or exclude expert testimony should be reviewed under an abuse of discretion standard rather than de novo (from scratch). The plaintiff, Robert Joiner, had worked as an electrician and was exposed to chemicals produced by General Electric and other companies which he claimed caused his lung cancer. He presented expert witnesses who testified that these chemicals could have promoted his disease but did not establish a direct cause-and-effect relationship between exposure and illness. The District Court excluded this testimony for lack of reliability, leading to summary judgment in favor of GE; the Eleventh Circuit reversed on appeal using de novo review standards for admissibility decisions regarding scientific evidence. The Supreme Court disagreed with the appellate court’s approach, stating it overstepped its authority by failing to apply an "abuse-of-discretion" standard when reviewing lower courts' evidentiary rulings - essentially giving too much weightage to unproven scientific theories without sufficient basis in established fact or methodology.

In the dissenting opinion for General Electric Company, et al. v. Robert K. Joiner Et Ux., Justice Stevens argued that the majority's decision to overturn the lower court's ruling was inappropriate because it did not give due deference to a trial judge’s discretion in deciding whether or not expert testimony is admissible evidence. He believed that this case should have been treated as an abuse of discretion review rather than de novo (starting anew). According to him, there was no clear error in judgment by the District Court when they decided to admit expert testimony linking PCB exposure with lung cancer based on animal studies and other scientific literature - despite acknowledging some gaps between these studies and human cases like Joiner’s. The dissent also expressed concern about how this decision could impact future toxic tort litigation by making it more difficult for plaintiffs who are victims of corporate negligence or misconduct related to environmental pollution or hazardous substances exposure.