United States v. Rodriguez, 2015 U.S. App. LEXIS 840 (11th Cir. Jan. 21, 2015):

We have previously held that the overruling of a motion in limine does not preserve an evidentiary issue for appeal. United States v. Rutkowski, 814 F.2d 594, 598 (11th Cir. 1987) (per curiam). Rather, an objection at trial is required to preserve an issue. Id. The Court has noted that a motion in limine is insufficient to preserve an evidentiary issue because it may address hypothetical concerns that may not arise during the course of a trial. United States v. Khoury, 901 F.2d 948, 966 (11th Cir. 1990), modified on other grounds, 910 F.2d 713 (11th Cir. 1990). However, as of the 2000 amendments, the Federal Rules of Evidence state that a "definitive" pre-trial ruling need not be renewed to preserve the issue for appeal. Fed. R. Evid. 103(b).

Federal Rule of Evidence 702 governs the admissibility of expert testimony. A qualified witness may offer expert testimony if: (a) the witness's scientific, technical or specialized knowledge is helpful to a trier of fact; (b) the testimony is based on sufficient facts or data; (c) the testimony is the product of reliable principles and methods; and (d) the witness reliably applied the principles [*3]  and methods to the facts of the case. Fed. R. Evid 702. Under Daubert, the trial court must determine whether an expert's testimony is based on reasoning or methodology that is scientifically valid and whether that methodology can be applied to the facts at issue. Daubert, 509 U.S. at 592-93, 113 S. Ct. at 2796; see also Kumho Tire Co., 526 U.S. at 141, 119 S. Ct. at 1171 (clarifying that Daubert applies to all expert testimony, not just scientific testimony). Kumho Tire Co. makes clear, however, that while the court must serve as a gatekeeper, it need not conduct a formal hearing "where the reliability of an expert's methods is properly taken for granted . . . ." 526 U.S. at 152, 119 S. Ct. at 1176.

As an initial matter, while the government argues otherwise, we treat this issue as preserved. The district court issued a definitive pre-trial ruling on the admissibility of Magnuson's testimony. Accordingly, the defendants were not required to renew their pre-trial objection to his status as an expert. See Fed. R. Evid. 103(b).

As to the Daubert issue, it is clear that a district court need not conduct a Daubert hearing where one would be unnecessary. See Kumho Tire Co., 526 U.S. at 152, 119 S. Ct. at 1176. The court here, in large part, declined to hold a hearing because it had available to it the testimony of the same witness, on the near identical issue, [*4]  from a case before a different judge in the same court. Rodriguez and Robinson, neither here nor below, have argued that the two cases presented a different question. If anything, the testimony in this case was less controversial than in the previous case, as Magnuson did not testify here that a cell phone call necessarily connects to the nearest tower, but more generally testified that a cell phone cannot connect to a tower that is outside its range, and stated that his maps were based on estimates of cell phone ranges. The minimal reliability of that conclusion, required by Daubert, could be said to be "properly taken for granted," such that a hearing was not warranted. See Kumho Tire Co., 526 U.S. at 152, 119 S. Ct. at 1176. Accordingly, we conclude that the district court did not abuse its discretion in not holding a Daubert hearing.