Sania Mahmood was driving on the New Jersey Turnpike in June 2007 when a tractor-trailer moved into her lane and collided with her vehicle, causing her to crash into the center median of the highway.

Mahmood filed a complaint in the Superior Court of New Jersey in May 2009 against the driver and his company, which was subsequently removed to the United States District Court. 

The parties stipulated to the liability of the Defendants, so the only issue at trial was damages. The jury awarded Mahmood $25,000 in compensatory damages, and the court denied her motion for a new trial. On appeal, Mahmood argued that the trial judge made several errors, among which was curtailing the expert testimony of Dr. SK and prematurely excluding portions of the expert’s medical conclusions. 
Circuit Judge Joseph A. Greenaway of the United States Court of Appeals, Third Circuit wrote in the opinion that in Daubert v. Merrell Dow Pharmaceuticals (U.S. 1993), the Supreme Court held that “[f]aced with a proffer of expert scientific testimony … the trial judge must determine at the outset … 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.” Under Daubert, courts must address a “trilogy of restrictions” before permitting the admission of expert testimony: 
1. Qualification;
2. Reliability; and 
3. Fitness 
The party offering the expert has to prove each of these requirements by a preponderance of the evidence. 
Judge Greenaway explained that in this case, the defense counsel filed a motion to preclude Dr. SK, a licensed medical doctor, from testifying on several conclusions reached in his reports. After the District Court heard oral argument on the issue, it issued an order granting the motion.  The portions excluded by the District Court included SK’s recommendation that Mahmood undergo cervical fusion surgery.
The District Court, Judge Greenaway wrote, appeared to have determined that Dr. SK’s findings failed to meet the “reliability” prong of Daubert. This requirement “means that the expert’s opinion must be based on the ‘methods and procedures of science’ rather than on ‘subjective belief or unsupported speculation’; the expert must have ‘good grounds’ for his or her belief.” 
Dr. SK’s reports met the other two prongs of the Daubert analysis. The District Court’s order correctly implied that Dr. SK met the “qualification” prong. The Court of Appeals agreed.
Judge Greenaway reasoned that, while it was possible that Dr. SK had an independent basis to reach conclusions in his reports, there was little in the way of analysis—beyond a list of sources he reviewed—to show how he reached his conclusions. There was a "tenuous" link between the sources consulted and the conclusions reached in Dr. SK’s reports, Greenaway wrote. “There are insufficient references in the Plaintiff’s medical records and reports of other physicians to support this opinion.” The record indicated that Dr. SK relied on another doctor’s findings to recommend cervical fusion surgery. However, that doctor’s report merely identified cervical spine anterior fusion as a treatment of last resort. The defense also conceded that this doctor wasn’t going to testify about the need for cervical surgery—which removed what Judge Greenaway called a significant basis for how Dr. SK came to his conclusion. Based on this scenario, the Third Circuit held that it wasn’t unreasonable for the District Court to find Dr. SK’s reports to be unreliable. 
Mahmood argued that the record was insufficiently developed for the District Court to preclude Dr. SK from testifying as to the medical issues. The District Court heard oral argument on the motions, where the trial counsel for Mahmood was unable to produce satisfactory answers as to how SK reached his conclusions. While the Court of Appeals continued to endorse the view that medical reports need not contain elaborate details concerning the findings, it also recognized that “the law grants a district court the same broad latitude when it decides how to determine reliability as it enjoys in respect to its ultimate reliability determination.” 
Accordingly, the Court of Appeals affirmed the District Court’s ruling on the expert testimony. Mahmood v. Narciso, — Fed.Appx. —-, 2013 WL 6610127 (C.A.3 (N.J.) Dec. 17, 2013).