There is no such motion in the Federal Rules
No rule of civil procedure or evidence creates a “Daubert motion.” The phrase is practitioner shorthand for a Rule 702 argument, and the argument travels on an ordinary vehicle: a motion in limine, a motion to exclude or strike expert testimony, an objection at trial, or a component of a summary-judgment motion where exclusion is dispositive of an element. Some commentators argue the label should be retired in favor of “Rule 702 motion,” now that the rule's own text carries the burden and the standard.
The choice of vehicle is not cosmetic. A motion in limine is governed by the pretrial order and is often decided provisionally. A motion to strike an opinion filed alongside summary judgment puts the admissibility question in front of the court at the moment it decides whether a record supports a claim, which is why exclusion motions against causation experts are so often filed that way. A trial objection preserves the point but forfeits the ability to shape the record in advance.
The deadline is in the scheduling order, not in a rule
FRCP 26(a)(2)(D) supplies default disclosure timing — 90 days before trial, and 30 days after the opposing disclosure for rebuttal — “absent a stipulation or a court order,” and in practice a court order almost always displaces it. Most districts set a separate expert-challenge deadline in the FRCP 16(b) scheduling order, frequently keyed to the close of expert discovery rather than to trial. Missing that deadline can waive the challenge, and the risk is real enough that the date belongs on the calendar the day the order issues.
The sequence that produces a usable motion runs backwards from that date: report served, deposition taken after the report as FRCP 26(b)(4)(A) requires, transcript received and reviewed, motion filed. Compressing the deposition against the motion deadline is the most common way a challenge ends up briefed without the admissions it needed.
What the local rules require in the papers
The mechanics come from local rules and the judge's standing order, and they are more specific than most practitioners expect. A representative standing order in the Northern District of Illinois requires the movant to “identify the specific opinion(s) that the movant seeks to exclude and the legal basis for exclusion, together with sufficient background information to provide context,” and to file “the relevant expert report(s) and, if the expert was deposed, the full transcript of the expert's deposition” in searchable format. It provides that the court “may conduct a Daubert hearing” on request or on its own motion, and states that the proponent bears the burden.
Three requirements recur across such orders and are worth treating as universal even where they are not written down. Identify opinions, not the witness. Attach the primary record — the report and the full transcript, not excerpts selected by the movant. And provide enough context that a judge unfamiliar with the discipline can follow what the method is supposed to do before being told what went wrong with it.
Structuring the motion element by element
Rule 702 has four elements and the motion should be organized by them, because that is how the ruling will be written. For each challenged opinion: is the witness qualified for this opinion; will it help the trier of fact under 702(a); is it based on sufficient facts or data under 702(b); is it the product of reliable principles and methods under 702(c); and does the opinion reflect a reliable application of those principles and methods to the facts of this case under 702(d).
The distinction between (c) and (d) carries most of the weight in modern practice. Attacking the method itself is difficult where the method is an accepted one in the field. Attacking the application — the method was stated but not performed, or performed on data that will not support the step taken — is the argument the 2023 amendment to (d) was written to protect. The Advisory Committee described the amended subsection as emphasizing “that each expert opinion must stay within the bounds of what can be concluded from a reliable application of the expert's basis and methodology.”
Motions that ask the court to disqualify a person tend to fail. Motions that ask the court to strike opinions three, five and six, and to limit opinion two to what the underlying data supports, ask for the relief courts most often grant.
How many opinions to challenge is a judgment about credibility rather than about page limits. A motion that attacks every opinion in a report, including those with obvious support, invites the court to read the whole filing as reflexive and to deny it as a unit. A motion that concedes the unassailable opinions and identifies three that are not tells the court where to look, and the concession itself costs nothing that cross-examination could have recovered.
Building the motion on the record you already have
Because FRE 104(a) frees the court from the rules of evidence on a preliminary question, the motion is supported by the report and the deposition transcript rather than by admissible trial evidence. The strongest version of the motion is one in which every proposition is a citation to the expert's own testimony: the expert agreed the method requires step X; the expert agreed step X was not performed; the expert agreed the data set does not distinguish between the two explanations; the expert agreed the conclusion rests on an assumption supplied rather than tested.
Motions built instead on the movant's characterization of what a competent analysis would have looked like invite the answer that the movant is arguing the merits. Where the record genuinely does not contain the concession, a supporting declaration from a rebuttal expert is the usual substitute — with the understanding that it invites a reciprocal challenge and puts a second methodology in front of the court.
Two record problems recur. The first is a transcript cited in fragments, where the answer relied on is qualified two pages later; local rules that require the full transcript exist partly because opponents reliably supply the rest. The second is an errata sheet served after the deposition that softens the admission the motion is built on. Both are better addressed in the opening brief than in reply, where the movant has no further opportunity to answer.
How the opposition is written
The opposition brief is not a mirror image, because the burden is not symmetrical. The proponent has to affirmatively establish each element by a preponderance, so an opposition that only rebuts the movant's points leaves the record without a showing. The effective structure is to state the method, show where in the report and transcript each element is satisfied, and only then answer the attack.
The most-quoted sentence in expert-admissibility oppositions comes from Daubert itself, 509 U.S. at 596: “Vigorous cross-examination, presentation of contrary evidence, and careful instruction on the burden of proof are the traditional and appropriate means of attacking shaky but admissible evidence.” It remains good law, and the operative words are “shaky but admissible.” The sentence presupposes that the Rule 104(a) gate has been passed; it is not itself a rule of admissibility, and the 2023 amendment was aimed squarely at courts that had read it as a presumption.
What an opposition can still say, on the Committee's own authority: that Rule 104(a) “does not require perfection”; that nothing requires a court “to nitpick an expert's opinion in order to reach a perfect expression of what the basis and methodology can support”; that an expert who “has not read every single study that exists” raises a question of weight; that requiring testimony to “appreciably help” the trier of fact is “unnecessarily strict”; and that where experts differ on contested facts, the jury can decide which to credit.
The weight argument after December 2023
The 2023 amendment narrowed the “goes to weight” response without abolishing it. The Advisory Committee wrote that “many courts have held that the critical questions of the sufficiency of an expert's basis, and the application of the expert's methodology, are questions of weight and not admissibility,” and that “[t]hese rulings are an incorrect application of Rules 702 and 104(a).” An opposition that rests on a pre-2023 circuit decision announcing a general rule that factual basis goes to credibility is resting on precisely the class of holding the Committee identified.
The distinction that survives is one of order. Once the court has found it more likely than not that an admissibility requirement is met, the Committee said, “any attack by the opponent will go only to the weight of the evidence.” Weight is what remains after the gate, not a reason to skip it — and FRE 104(e) is the textual home of everything that remains.
Whether a given circuit's older “weight, not admissibility” precedent survives is live litigation, not settled doctrine, and briefs on both sides are better served by acknowledging that than by asserting a national position.
Reply, ruling, and preservation
Replies are where challenges are lost through overreach. A reply that raises a new ground — a qualification argument that appeared nowhere in the motion, an attack on an opinion not previously identified — invites a sur-reply or is disregarded, and either outcome costs the movant the last word on the arguments actually made. The disciplined reply answers the opposition's characterization of the transcript and stops.
Rulings come in more than two shapes. A court may grant in part, may admit the opinion but limit its scope, may defer the question to trial and take it up on voir dire when the foundation is laid, or may deny without prejudice to renewal at trial. Where the ruling is provisional, the objection has to be renewed to be preserved; FRE 103(b) provides that once the court rules definitively on the record, renewal is not required.
On appeal the standard is abuse of discretion under General Electric Co. v. Joiner, 522 U.S. 136 (1997), and Kumho Tire extends that deference to the court's choices about how to test reliability. Both an admission and an exclusion supported by specific findings are difficult to disturb. That is the strongest practical reason to make the complete argument once, in the district court, on a record that will read the same way to a court of appeals as it did to the judge who ruled.
Rule text and both Committee notes: Federal Rule of Evidence 702. Disclosure and deposition sequencing: Federal Rule of Civil Procedure 26.
Frequently Asked Questions
What is a Daubert motion called in the Federal Rules?
Nothing — there is no Daubert motion in the rules. The argument is brought as a motion in limine, a motion to exclude or strike expert testimony, part of a summary-judgment motion where exclusion is dispositive, or an objection at trial. The label is practitioner shorthand, and some commentators now prefer "Rule 702 motion" because the rule's text carries the standard and the burden. What controls the mechanics is the local rules and the judge's standing order.When is the deadline to move to exclude an expert?
It comes from the Rule 16(b) scheduling order, not from a national rule. FRCP 26(a)(2)(D) supplies default disclosure timing of 90 days before trial and 30 days after an opposing disclosure for rebuttal, but that default is almost always displaced by court order. Most districts set a separate expert-challenge deadline, often keyed to the close of expert discovery. Missing it can waive the challenge, so the date belongs on the calendar when the scheduling order issues.What has to be filed with the motion?
Local rules and standing orders control. A representative standing order requires the movant to identify the specific opinions to be excluded and the legal basis, provide enough background for context, and file the relevant expert reports and the full deposition transcript in searchable format. Filing selected excerpts rather than the complete transcript is a common source of friction, because the court deciding a Rule 104(a) question is entitled to the whole record the parties are arguing about.Should the motion attack the expert or the opinions?
The opinions. Each element of Rule 702 applies to each opinion, and qualification is assessed opinion by opinion rather than witness by witness. Partial exclusion — striking some opinions, limiting others to what the data supports, admitting the rest — is a far more common outcome than wholesale disqualification. A motion drafted to identify specific opinions and the specific element each one fails asks for the relief courts most often grant.Does "it goes to weight" still work as an opposition?
More narrowly than before December 2023. The Advisory Committee wrote that holdings treating sufficiency of basis and application of methodology as questions of weight rather than admissibility "are an incorrect application of Rules 702 and 104(a)." What survives is the sequencing point the Committee also made: once the court finds an admissibility requirement more likely than not satisfied, any further attack goes to weight. Whether a given circuit's older weight precedent survives is currently being litigated.What can a proponent quote back from the Committee note?
Several passages cut toward admission. The Rule 104(a) standard "does not require perfection" and nothing requires a court "to nitpick an expert's opinion." An expert who has not read every study raises a weight question. Courts demanding that testimony "appreciably help" the trier of fact apply a standard the Committee called "unnecessarily strict." And where experts reach different conclusions on contested facts, the note says the jury can decide which side's experts to credit.What is the standard of review if the motion is denied?
Abuse of discretion, under General Electric Co. v. Joiner, 522 U.S. 136 (1997), which rejected more searching review of evidentiary rulings on expert testimony. Kumho Tire extends the same deference to the trial court's decisions about how to test reliability, not merely to the ultimate ruling. The practical consequence is symmetrical: admissions and exclusions supported by specific findings are both difficult to disturb, which puts the weight of the exercise in the district court.Published