Daubert factors in Delaware

2025Bancorporation, Inc. v. Le Beau, 737 A.2d 513, 521 (Del. 1999) (adopting the Daubert standard as the correct interpretation of Delaware Rule of Evidence 702)). based on sufficient facts or data, be the product of reliable principles and methods, and the expert must have reliably applied these principles and methods to the case facts.8 Our Supreme Court has adopted a five-part test for the admissibility of expert testimony, requiring the judge to determine whether (1) the witness is qualified in the relevant discipline, (2) the evidence is relevant and reliable, (3) the expert’s opinion is base

2025Bancorporation, Inc. v. Le Beau, 737 A.2d 513, 521 (Del. 1999) (adopting the Daubert standard as the correct interpretation of Delaware Rule of Evidence 702)). based on sufficient facts or data, be the product of reliable principles and methods, and the expert must have reliably applied these principles and methods to the case facts.8 Our Supreme Court has adopted a five-part test for the admissibility of expert testimony, requiring the judge to determine whether (1) the witness is qualified in the relevant discipline, (2) the evidence is relevant and reliable, (3) the expert’s opinion is base

2025Bancorporation, Inc. v. Le Beau, 737 A.2d 513, 521 (Del. 1999) (adopting the Daubert standard as the correct interpretation of Delaware Rule of Evidence 702)). 6 Daubert v. Merrell Dow Pharm., Inc., 509 U.S. 579, 595 (1993))). 7 Sturgis v. Bayside Health Ass'n, 942 A.2d 579, 584 (Del. 2007) (citing Daubert v. Merrell Dow Pharm., Inc., 509 U.S. 579, 595 (1993))). 6 instruction on the burden of proof are the traditional and appropriate means of attacking… admissible evidence.”8 DISCUSSION A. Admissibility Of Proffered Expert Testimony Proposed By The State.

2025Bancorporation, Inc. v. Le Beau, 737 A.2d 513, 521 (Del. 1999) (adopting the Daubert standard as the correct interpretation of Delaware Rule of Evidence 702)). 6 Daubert v. Merrell Dow Pharm., Inc., 509 U.S. 579, 595 (1993))). 7 Sturgis v. Bayside Health Ass'n, 942 A.2d 579, 584 (Del. 2007) (citing Daubert v. Merrell Dow Pharm., Inc., 509 U.S. 579, 595 (1993))). 6 instruction on the burden of proof are the traditional and appropriate means of attacking… admissible evidence.”8 DISCUSSION A. Admissibility Of Proffered Expert Testimony Proposed By The State.

2025Relevant to the claims on appeal, the Superior Court found that: (1) the “general causation” question in the case “focuses on NDMA,” 40 and the experts’ general causation opinions therefore could be based on studies relating to the 37 Id. at *27–29. 38 Id. at *29–30. 39 Id. at *31. 40 Id. at *7. 15 ingestion of NDMA, rather than ranitidine itself;41 (2) Delaware law does not “recognize a ‘threshold dose’ requirement as part of the general causation analysis”;42 and (3) in performing its role as a gatekeeper and conducting a Daubert analysis, the trial court should rule “with a ‘liberal thrust’

2025Relevant to the claims on appeal, the Superior Court found that: (1) the “general causation” question in the case “focuses on NDMA,” 40 and the experts’ general causation opinions therefore could be based on studies relating to the 37 Id. at *27–29. 38 Id. at *29–30. 39 Id. at *31. 40 Id. at *7. 15 ingestion of NDMA, rather than ranitidine itself;41 (2) Delaware law does not “recognize a ‘threshold dose’ requirement as part of the general causation analysis”;42 and (3) in performing its role as a gatekeeper and conducting a Daubert analysis, the trial court should rule “with a ‘liberal thrust’

2025DuPont de Nemours & Co., 906 A.2d 787, 795 (Del. 2006)). 15 D.R.E. 702. 5 (3) the expert’s opinion is based upon information reasonably relied upon by experts in the particular field; (4) the expert testimony will assist the trier of fact to understand the evidence or to determine a fact in issue; and (5) the expert testimony will not create unfair prejudice or confuse or mislead the jury.16 In applying this Daubert-Bowen test for the admissibility of expert evidence, trial courts act as gatekeepers rather than factfinders, focused on whether the proffered evidence is “relevant” and “reliable”

2025DuPont de Nemours & Co., 906 A.2d 787, 795 (Del. 2006)). 15 D.R.E. 702. 5 (3) the expert’s opinion is based upon information reasonably relied upon by experts in the particular field; (4) the expert testimony will assist the trier of fact to understand the evidence or to determine a fact in issue; and (5) the expert testimony will not create unfair prejudice or confuse or mislead the jury.16 In applying this Daubert-Bowen test for the admissibility of expert evidence, trial courts act as gatekeepers rather than factfinders, focused on whether the proffered evidence is “relevant” and “reliable”

2023Motions to Exclude Expert Witnesses The Delaware Supreme Court has adopted the Daubert standard to determine the admissibility of expert testimony.26 Under this standard, the Court asks whether: (i) the witness is “qualified as an expert by knowledge, skill, experience, training or education;” (ii) the evidence is relevant and reliable; (iii) the expert’s opinion is based upon information “reasonably relied upon by experts in the particular field;” (iv) the expert testimony will “assist the trier of fact to understand the evidence or 26 See Eskin v. Carden, 842 A.2d 1222, 1231 (Del. 2004) (cit

2023Motions to Exclude Expert Witnesses The Delaware Supreme Court has adopted the Daubert standard to determine the admissibility of expert testimony.26 Under this standard, the Court asks whether: (i) the witness is “qualified as an expert by knowledge, skill, experience, training or education;” (ii) the evidence is relevant and reliable; (iii) the expert’s opinion is based upon information “reasonably relied upon by experts in the particular field;” (iv) the expert testimony will “assist the trier of fact to understand the evidence or 26 See Eskin v. Carden, 842 A.2d 1222, 1231 (Del. 2004) (cit

2024Bancorporation, Inc. v. Le Beau, 737 A.2d 513, 521 (Del. 1999). 21 D.R.E. 702. 22 Bowen, 906 A.2d 787, 794 (Del. 2006) (citing Daubert, 509 U.S. at 592 ). 23 Daubert, 509 U.S. at 589 . 24 Kuhmo Tire Co., Ltd. v. Carmichael, 526 U.S. 137, 150 (quoting Daubert, 509 U.S. at 594 ). 25 Opening Br. at 20. 14 widely from laboratory to laboratory” and that Cadenas “premise[d] [the DNA Labs Report’s] results on ‘if’ and likelihood ratios containing no concrete and scientifically accepted practices.”26 Hudson also argues that a Daubert hearing was necessary to test the admissibility of the State’s proff

2024Bancorporation, Inc. v. Le Beau, 737 A.2d 513, 521 (Del. 1999). 21 D.R.E. 702. 22 Bowen, 906 A.2d 787, 794 (Del. 2006) (citing Daubert, 509 U.S. at 592 ). 23 Daubert, 509 U.S. at 589 . 24 Kuhmo Tire Co., Ltd. v. Carmichael, 526 U.S. 137, 150 (quoting Daubert, 509 U.S. at 594 ). 25 Opening Br. at 20. 14 widely from laboratory to laboratory” and that Cadenas “premise[d] [the DNA Labs Report’s] results on ‘if’ and likelihood ratios containing no concrete and scientifically accepted practices.”26 Hudson also argues that a Daubert hearing was necessary to test the admissibility of the State’s proff

2024Defendants assert several of the studies Mannen relies on have not been subjected to peer review.77 Defendants argue Mannen’s “easier-to-roll” hypothesis is unsupported by the studies she cites.78 As to Mannen’s conclusion that a side-facing infant would come into contact with the side of the RnP, leading to an increased risk in suffocation, Defendants posit Mannen’s demonstration using a soccer ball in place of an infant “is not based on any recognized methodology for examining potential respiratory compromises.”79 This Court possesses “broad latitude to determine whether any or all of the Da

2024Defendants assert several of the studies Mannen relies on have not been subjected to peer review.77 Defendants argue Mannen’s “easier-to-roll” hypothesis is unsupported by the studies she cites.78 As to Mannen’s conclusion that a side-facing infant would come into contact with the side of the RnP, leading to an increased risk in suffocation, Defendants posit Mannen’s demonstration using a soccer ball in place of an infant “is not based on any recognized methodology for examining potential respiratory compromises.”79 This Court possesses “broad latitude to determine whether any or all of the Da

2019STANDARD FOR ADMISSIBILITY OF EXPERT TESTIMONY The Delaware Supreme Court has adopted the Daubert standard to determine the admissibility of expert testimony.23 Under this standard, the Court asks whether: (i) the witness is “qualified as an expert by knowledge, skill, experience, training or education;” (ii) the evidence is relevant and reliable; (iii) the expert’s opinion is based upon information “reasonably relied upon by experts in the particular field;” (iv) the expert testimony will “assist the trier of fact to understand the evidence or 23 See Eskin v. Carden, 842 A.2d 1222, 1231 (Del.

2019STANDARD FOR ADMISSIBILITY OF EXPERT TESTIMONY The Delaware Supreme Court has adopted the Daubert standard to determine the admissibility of expert testimony.23 Under this standard, the Court asks whether: (i) the witness is “qualified as an expert by knowledge, skill, experience, training or education;” (ii) the evidence is relevant and reliable; (iii) the expert’s opinion is based upon information “reasonably relied upon by experts in the particular field;” (iv) the expert testimony will “assist the trier of fact to understand the evidence or 23 See Eskin v. Carden, 842 A.2d 1222, 1231 (Del.

2024Co., 795 F. App’x 128 , 131 (3d Cir. 2020) (citing Oddi with approval and upholding district court’s decision that a Daubert hearing was unnecessary because the trial court had a sufficient record to rely upon, including the expert report itself and the parties’ submissions, and because movant failed to explained how a hearing would have benefited consideration of the issue); see also Minner, 791 A.2d at 845 (“While the matter is always discretionary, absent a special reason and need to have the hearings, requests for them should generally be denied.

2024Co., 795 F. App’x 128 , 131 (3d Cir. 2020) (citing Oddi with approval and upholding district court’s decision that a Daubert hearing was unnecessary because the trial court had a sufficient record to rely upon, including the expert report itself and the parties’ submissions, and because movant failed to explained how a hearing would have benefited consideration of the issue); see also Minner, 791 A.2d at 845 (“While the matter is always discretionary, absent a special reason and need to have the hearings, requests for them should generally be denied.

2021Ct. Aug. 29, 2018) (observing “that a rigid application of the Daubert factors simply cannot be engaged to determine testimonial reliability in every field of expertise.”). 24 Norman v. All About Women, P.A., 193 A.3d 726, 730 (Del. 2018) (citation omitted). 25 See, e.g.

2021Ct. Aug. 29, 2018) (observing “that a rigid application of the Daubert factors simply cannot be engaged to determine testimonial reliability in every field of expertise.”). 24 Norman v. All About Women, P.A., 193 A.3d 726, 730 (Del. 2018) (citation omitted). 25 See, e.g.

2025The Superior Court’s “liberal thrust” standard The Superior Court, before engaging in its Daubert analysis, noted that courts are directed to “conduct their Daubert analyses ‘with a liberal thrust favoring admission.’”81 The phrase “liberal thrust” is taken from Daubert itself, but the Superior Court adopted the phrase in a manner that divorced it from its context.82 In Daubert, the United States Supreme Court explained that the Frye test that previously governed expert testimony had imposed a “rigid ‘general acceptance’ requirement” on admissibility that was not consistent with the “liberal t

2025The Superior Court’s “liberal thrust” standard The Superior Court, before engaging in its Daubert analysis, noted that courts are directed to “conduct their Daubert analyses ‘with a liberal thrust favoring admission.’”81 The phrase “liberal thrust” is taken from Daubert itself, but the Superior Court adopted the phrase in a manner that divorced it from its context.82 In Daubert, the United States Supreme Court explained that the Frye test that previously governed expert testimony had imposed a “rigid ‘general acceptance’ requirement” on admissibility that was not consistent with the “liberal t

2023Therefore, the Supreme Court held that plaintiff’s expert rendered an “opinion based upon a completely incorrect case specific factual predicate.”41 This case is not comparable to Perry or any of the other cases cited by Urban and Schmitz.42 Urban and Schmitz have not pointed to any incorrect facts or data 38 509 U.S. 579 (1993). 39 Perry v. Berkley, 996 A.2d 1262, 1267 (Del. 2010) (citations omitted). 40 Id. 41 Id. at 1271 . (emphasis in original). 42 The Court, after oral argument, requested that the parties address the issue of whether a court had ever granted a Daubert motion for failure t

2023Therefore, the Supreme Court held that plaintiff’s expert rendered an “opinion based upon a completely incorrect case specific factual predicate.”41 This case is not comparable to Perry or any of the other cases cited by Urban and Schmitz.42 Urban and Schmitz have not pointed to any incorrect facts or data 38 509 U.S. 579 (1993). 39 Perry v. Berkley, 996 A.2d 1262, 1267 (Del. 2010) (citations omitted). 40 Id. 41 Id. at 1271 . (emphasis in original). 42 The Court, after oral argument, requested that the parties address the issue of whether a court had ever granted a Daubert motion for failure t

2020ANALYSIS The Daubert Standard Delaware has adopted the Daubert standard for the admissibility of expert testimony.’ Under Daubert, an expert may testify to his opinions (and, in cases such as this, those opinions may form the basis of a prima facie case)® if the testimony meets the following criteria: (1) the witness is qualified as an expert by knowledge, skill experience, training or education; (2) the evidence is relevant; (3) the expert's opinion is based upon information reasonably relied upon by experts in the particular field; (4) the expert testimony will assist the trier of fact to un

2020ANALYSIS The Daubert Standard Delaware has adopted the Daubert standard for the admissibility of expert testimony.’ Under Daubert, an expert may testify to his opinions (and, in cases such as this, those opinions may form the basis of a prima facie case)® if the testimony meets the following criteria: (1) the witness is qualified as an expert by knowledge, skill experience, training or education; (2) the evidence is relevant; (3) the expert's opinion is based upon information reasonably relied upon by experts in the particular field; (4) the expert testimony will assist the trier of fact to un

2023Given that many fields of expertise are not subject to peer review and publication, Delaware courts instruct against the rigid application of Daubert factors to determine reliability of expert evidence.14 As a result, trial courts possess “broad 12 See Rodriguez v. State, 30 A.3d 764, 769-70 (Del. 2011) (“Like expert witnesses generally, an analyst’s lack of proper training or deficiency in judgment may be disclosed in cross-examination.

2019STANDARD FOR ADMISSIBILITY OF EXPERT TESTIMONY The Delaware Supreme Court has adopted the Daubert standard to determine the admissibility of expert testimony.23 Under this standard, the Court asks whether: (i) the witness is “qualified as an expert by knowledge, skill, experience, training or education;” (ii) the evidence is relevant and reliable; (iii) the expert’s opinion is based upon information “reasonably relied upon by experts in the particular field;” (iv) the expert testimony will “assist the trier of fact to understand the evidence or 23 See Eskin v. Carden, 842 A.2d 1222, 1231 (Del.

2020Rather, the trial judge’s role as gatekeeper11 is limited to determining “whether the proponent of the evidence has demonstrated that scientific conclusions have been generated using sound and reliable approaches.”12 Expert opinions are admissible where they assist the trier of fact in understanding the facts or evidence presented at 8 Id. 9 Id. 10 Pavey v. Kalish, 2010 WL 3294304, at *3 (Del. 2010); Sturgis v. Bayside Health Ass’n, 942 A.2d 579, 584 (Del. 2007). 11 Id. at 583 . 12 State v. McMullen, 900 A.2d 103, 114 (Del.

2020Rather, the trial judge’s role as gatekeeper11 is limited to determining “whether the proponent of the evidence has demonstrated that scientific conclusions have been generated using sound and reliable approaches.”12 Expert opinions are admissible where they assist the trier of fact in understanding the facts or evidence presented at 8 Id. 9 Id. 10 Pavey v. Kalish, 2010 WL 3294304, at *3 (Del. 2010); Sturgis v. Bayside Health Ass’n, 942 A.2d 579, 584 (Del. 2007). 11 Id. at 583 . 12 State v. McMullen, 900 A.2d 103, 114 (Del.

2020Bancorporation, Inc. v. Le Beau, 737 A.2d 513, 521 (Del. 1999) (adopting the Daubert standard as the correct interpretation of Delaware Rule of Evidence 702). 23 Id. 24 Id. 25 Pavey v. Kalish, 2010 WL 3294304, at *3 (Del.

2020Bancorporation, Inc. v. Le Beau, 737 A.2d 513, 521 (Del. 1999) (adopting the Daubert standard as the correct interpretation of Delaware Rule of Evidence 702). 23 Id. 24 Id. 25 Pavey v. Kalish, 2010 WL 3294304, at *3 (Del.

2018The appeals court went on to affirm the admissibility of the EDR data on the alternative ground that there was “ general acceptance of data from motor vehicle crash recorders in the relevant scientific community.”12 Though Massachusetts is 9 Ia’. (quoting Commonwealth v. Patters0n, 840 N.E.2d 12, 24 (Mass. 2005) (emphasis in original)). 10 Id. at 1220. ll ld 12 Id. at 1220_21. nominally a Daubert jurisdiction, the Zimmerman court admitted the evidence without performing a complete Daubert analysis.

2018The appeals court went on to affirm the admissibility of the EDR data on the alternative ground that there was “ general acceptance of data from motor vehicle crash recorders in the relevant scientific community.”12 Though Massachusetts is 9 Ia’. (quoting Commonwealth v. Patters0n, 840 N.E.2d 12, 24 (Mass. 2005) (emphasis in original)). 10 Id. at 1220. ll ld 12 Id. at 1220_21. nominally a Daubert jurisdiction, the Zimmerman court admitted the evidence without performing a complete Daubert analysis.

2018The Frye standard’s sole focus_the general acceptance of the evidence in the particular field in which it belongs$_is analogous to Daubert’s inquiry into the acceptance of 3 Id. at 1227 (quoting Cunningham v. McDonala', 689 A.2d 1190, 1193 (Del.1997)). 4 Sturgz's v. Bayside Health Ass ’n Chartered, 942 A.2d 579, 584 (Del. 2007). 5 Frye v. U.S., 293 F. 1013, 1014 (D.C.

2018Nonetheless, these cases are instructive The Frye standard’s sole focus_the general acceptance of the evidence in the particular field in which it belongs5_is analogous to Daubert’s inquiry into the acceptance of 3 Ia'. at 1227 (quoting Cunningham v. McDonald, 689 A.2d 1190, 1193 (Del.1997)). 4 Sturgis v. Baysz'de Health Ass ’n Chartered, 942 A.2d 579, 584 (Del. 2007). 5 Frye v. U.S., 293 F. 1013, 1014 (D.C.

2006See Minner, 791 A.2d at 848 citing Ruiz-Troche, 161 F.3d at 85 (in a Daubert analysis the court does not determine if the proffered science is correct or which of competing scientific views is superior). 172 .

2006See Minner, 791 A.2d at 848 citing Ruiz-Troche, 161 F.3d at 85 (in a Daubert analysis the court does not determine if the proffered science is correct or which of competing scientific views is superior). 172 .

2024Bancorporation, Inc. v. LeBeau, 737 A.2d 513, 522 (Del. 1999). 37 In re Asbestos Litig., 911 A.2d 1176, 1197 (Del.

2024Causation Experts’ Op. at 34; Ex. 75, at 6. 74 In re Asbestos Litig., 911 A.2d at 1207 . 75 The post-Daubert briefing here followed adjournment of the three-day Daubert hearing.

2025But the Grenier I court found that the Superior Court made certain factual findings at the Daubert hearing that were not supported by the record and therefore remanded the case for reconsideration of whether the challenged experts’ opinions created a “bridge, grounded in reliable science, between the scientific data regarding the association between unrefined chrysotile and asbestos-related diseases and the association between friction products and asbestos-related diseases.”127 The trial court then clarified its decision, and this Court affirmed, holding that the experts had “provide[d] the n

2025But the Grenier I court found that the Superior Court made certain factual findings at the Daubert hearing that were not supported by the record and therefore remanded the case for reconsideration of whether the challenged experts’ opinions created a “bridge, grounded in reliable science, between the scientific data regarding the association between unrefined chrysotile and asbestos-related diseases and the association between friction products and asbestos-related diseases.”127 The trial court then clarified its decision, and this Court affirmed, holding that the experts had “provide[d] the n

2024The trial judge had a sufficient record upon which to rely; namely, the expert report itself, a robust affidavit from DNA Labs employees Rachel Oeflein and Cristina Rentas detailing STRmix’s scientific reliability,59 and the parties’ submissions.60 58 See, e.g., Minner at 845–46 (quoting Weinstein’s Federal Evidence 2d § 702.5(2)(a)) (“The latitude provided by Kumho Tire allows the Court to decide ‘what proceedings, if any, are needed to investigate reliability.’”); United States v. Alatorre, 222 F.3d 1098 , 1103–04 (9th Cir. 2000) (holding trial court did not abuse its discretion when it allo

2024The trial judge had a sufficient record upon which to rely; namely, the expert report itself, a robust affidavit from DNA Labs employees Rachel Oeflein and Cristina Rentas detailing STRmix’s scientific reliability,59 and the parties’ submissions.60 58 See, e.g., Minner at 845–46 (quoting Weinstein’s Federal Evidence 2d § 702.5(2)(a)) (“The latitude provided by Kumho Tire allows the Court to decide ‘what proceedings, if any, are needed to investigate reliability.’”); United States v. Alatorre, 222 F.3d 1098 , 1103–04 (9th Cir. 2000) (holding trial court did not abuse its discretion when it allo

2024DuPont de Nemours & Co., 906 A.2d 787, 795 (Del. 2006) (internal quotations and citations omitted). 18 Wheeler v. State, 135 A.3d 282, 295 (Del. 2016). 19 Id. 13 request for a Daubert hearing.

2024DuPont de Nemours & Co., 906 A.2d 787, 795 (Del. 2006) (internal quotations and citations omitted). 18 Wheeler v. State, 135 A.3d 282, 295 (Del. 2016). 19 Id. 13 request for a Daubert hearing.

2024The Court still retains discretion as to whether to grant or deny such a request depending on the circumstances.”). 56 Kumho Tire Co., Ltd., 526 U.S. at 152 ; see also United States v. Alatorre, 222 F.3d 1098, 1100 (9th Cir. 2000). 57 See Alatorre, 222 F.3d at 1100 . 20 to fulfill its gatekeeping duties, the form of the proceeding is within their discretion.58 Based on this record, the Superior Court acted within its sound discretion in ruling on the admissibility of the State’s proffered expert testimony without first holding a Daubert hearing.

2024The Court still retains discretion as to whether to grant or deny such a request depending on the circumstances.”). 56 Kumho Tire Co., Ltd., 526 U.S. at 152 ; see also United States v. Alatorre, 222 F.3d 1098, 1100 (9th Cir. 2000). 57 See Alatorre, 222 F.3d at 1100 . 20 to fulfill its gatekeeping duties, the form of the proceeding is within their discretion.58 Based on this record, the Superior Court acted within its sound discretion in ruling on the admissibility of the State’s proffered expert testimony without first holding a Daubert hearing.