                      [J-92A-E-2019] [MO:Donohue, J.]
                IN THE SUPREME COURT OF PENNSYLVANIA
                            WESTERN DISTRICT


RICHARD THOMAS WALSH, EXECUTOR         :   No. 14 WAP 2019
OF THE ESTATE OF THOMAS J. WALSH,      :
DECEASED                               :   Appeal from the Order of the
                                       :   Superior Court entered June 20,
                                       :   2018 at No. 1661 WDA 2016
           v.                          :   vacating the Order of the Court of
                                       :   Common Pleas of Allegheny County
                                       :   entered October 14, 2016 at No. GD
BASF CORPORATION; BAYER                :   10-018588, and remanding.
CORPORATION D/B/A BAYER                :
CROPSCIENCE, L.P., AND BAYER           :   ARGUED: October 16, 2019
CROPSCIENCE HOLDING, INC., AND/OR      :
BAYER CROPSCIENCE, L.P. AND BAYER      :
CROPSCIENCE HOLDING, INC., IN THEIR    :
OWN RIGHT; BIOSAFE SYSTEMS, L.L.C.;    :
CHEMTURA CORPORATION; CLEARY           :
CHEMICAL CORP.; DOW                    :
AGROSCIENCES, L.L.C.; E.H. GRIFFITH,   :
INC.; E.I. DU PONT DE NEMOURS AND      :
CO., INC.; G.B. BIOSCIENCES            :
CORPORATION; JOHN DEERE                :
LANDSCAPING, INC., SUCCESSOR TO        :
LESCO, INC.; MONSANTO COMPANY;         :
NUFARM AMERICAS, INC.; REGAL           :
CHEMICAL CO.; SCOTTS-SIERRA CROP       :
PROTECTION CO.; AND SYNGENTA           :
CROP PROTECTION, INC.                  :
                                       :
                                       :
APPEAL OF: DOW AGROSCIENCES, LLC,      :
BAYER CROPSCIENCE, LP, BAYER           :
CORPORATION, AND BAYER                 :
CROPSCIENCE HOLDING, INC.              :

RICHARD THOMAS WALSH, EXECUTOR         :   No. 15 WAP 2019
OF THE ESTATE OF THOMAS J. WALSH,      :
DECEASED                               :   Appeal from the Order of the
                                       :   Superior Court entered June 20,
                                       :   2018 at No. 1661 WDA 2016,
           v.                          :   vacating the Order of the Court of
                                       :   Common Pleas of Allegheny County
                                        : entered October 14, 2016 at No. GD
BASF CORPORATION; BAYER                 : 10-018588, and remanding.
CORPORATION D/B/A BAYER                 :
CROPSCIENCE, L.P., AND BAYER            : ARGUED: October 16, 2019
CROPSCIENCE HOLDING, INC., AND/OR       :
BAYER CROPSCIENCE, L.P. AND BAYER       :
CROPSCIENCE HOLDING, INC., IN THEIR     :
OWN RIGHT; BIOSAFE SYSTEMS, L.L.C.;     :
CHEMTURA CORPORATION; CLEARY            :
CHEMICAL CORP.; DOW                     :
AGROSCIENCES, L.L.C.; E.H. GRIFFITH,    :
INC.; E.I. DU PONT DE NEMOURS AND       :
CO., INC.; G.B. BIOSCIENCES             :
CORPORATION; JOHN DEERE                 :
LANDSCAPING, INC., SUCCESSOR TO         :
LESCO, INC.; MONSANTO COMPANY;          :
NUFARM AMERICAS, INC.; REGAL            :
CHEMICAL CO.; SCOTTS-SIERRA CROP        :
PROTECTION CO.; AND SYNGENTA            :
CROP PROTECTION, INC.                   :
                                        :
                                        :
APPEAL OF: DEERE & COMPANY              :

RICHARD THOMAS WALSH, EXECUTOR          :   No. 16 WAP 2019
OF THE ESTATE OF THOMAS J. WALSH,       :
DECEASED                                :   Appeal from the Order of the
                                        :   Superior Court entered June 20,
                                        :   2018 at No. 1661 WDA 2016,
           v.                           :   vacating the Order of the Court of
                                        :   Common Pleas of Allegheny County
                                        :   entered October 14, 2016 at No. GD
BASF CORPORATION; BAYER                 :   10-018588, and remanding.
CORPORATION D/B/A BAYER                 :
CROPSCIENCE, L.P., AND BAYER            :   ARGUED: October 16, 2019
CROPSCIENCE HOLDING, INC., AND/OR       :
BAYER CROPSCIENCE, L.P. AND BAYER       :
CROPSCIENCE HOLDING, INC., IN THEIR     :
OWN RIGHT; BIOSAFE SYSTEMS, L.L.C.;     :
CHEMTURA CORPORATION; CLEARY            :
CHEMICAL CORP.; DOW                     :
AGROSCIENCES, L.L.C.; E.H. GRIFFITH,    :
INC.; E.I. DU PONT DE NEMOURS AND       :
CO., INC.; G.B. BIOSCIENCES             :
CORPORATION; JOHN DEERE                 :
LANDSCAPING, INC., SUCCESSOR TO         :



                   [J-92A-E-2019] [MO: Donohue, J.] - 2
LESCO, INC.; MONSANTO COMPANY;          :
NUFARM AMERICAS, INC.; REGAL            :
CHEMICAL CO.; SCOTTS-SIERRA CROP        :
PROTECTION CO.; AND SYNGENTA            :
CROP PROTECTION, INC.                   :
                                        :
                                        :
APPEAL OF: SYNGENTA CROP                :
PROTECTION, INC.                        :

RICHARD THOMAS WALSH, EXECUTOR          :   No. 17 WAP 2019
OF THE ESTATE OF THOMAS J. WALSH,       :
DECEASED                                :   Appeal from the Order of the
                                        :   Superior Court entered June 20,
                                        :   2018 at No. 1661 WDA 2016,
           v.                           :   vacating the Order of the Court of
                                        :   Common Pleas of Allegheny County
                                        :   entered October 14, 2016 at No. GD
BASF CORPORATION; BAYER                 :   10-018588, and remanding.
CORPORATION D/B/A BAYER                 :
CROPSCIENCE, L.P., AND BAYER            :   ARGUED: October 16, 2019
CROPSCIENCE HOLDING, INC., AND/OR       :
BAYER CROPSCIENCE, L.P. AND BAYER       :
CROPSCIENCE HOLDING, INC., IN THEIR     :
OWN RIGHT; BIOSAFE SYSTEMS, L.L.C.;     :
CHEMTURA CORPORATION; CLEARY            :
CHEMICAL CORP.; DOW                     :
AGROSCIENCES, L.L.C.; E.H. GRIFFITH,    :
INC.; E.I. DU PONT DE NEMOURS AND       :
CO., INC.; G.B. BIOSCIENCES             :
CORPORATION; JOHN DEERE                 :
LANDSCAPING, INC., SUCCESSOR TO         :
LESCO, INC.; MONSANTO COMPANY;          :
NUFARM AMERICAS, INC.; REGAL            :
CHEMICAL CO.; SCOTTS-SIERRA CROP        :
PROTECTION CO.; AND SYNGENTA            :
CROP PROTECTION, INC.                   :
                                        :
                                        :
APPEAL OF: MONSANTO COMPANY             :

RICHARD THOMAS WALSH, EXECUTOR          :   No. 18 WAP 2019
OF THE ESTATE OF THOMAS J. WALSH,       :
DECEASED                                :   Appeal from the Order of the
                                        :   Superior Court entered June 20,
                                        :   2018 at No. 1661 WDA 2016,



                   [J-92A-E-2019] [MO: Donohue, J.] - 3
               v.                                :   vacating the Order of the Court of
                                                 :   Common Pleas of Allegheny County
                                                 :   entered October 14, 2016 at No. GD
 BASF CORPORATION; BAYER                         :   10-018588, and remanding.
 CORPORATION D/B/A BAYER                         :
 CROPSCIENCE, L.P., AND BAYER                    :   ARGUED: October 16, 2019
 CROPSCIENCE HOLDING, INC., AND/OR               :
 BAYER CROPSCIENCE, L.P. AND BAYER               :
 CROPSCIENCE HOLDING, INC., IN THEIR             :
 OWN RIGHT; BIOSAFE SYSTEMS, L.L.C.;             :
 CHEMTURA CORPORATION; CLEARY                    :
 CHEMICAL CORP.; DOW                             :
 AGROSCIENCES, L.L.C.; E.H. GRIFFITH,            :
 INC.; E.I. DU PONT DE NEMOURS AND               :
 CO., INC.; G.B. BIOSCIENCES                     :
 CORPORATION; JOHN DEERE                         :
 LANDSCAPING, INC., SUCCESSOR TO                 :
 LESCO, INC.; MONSANTO COMPANY;                  :
 NUFARM AMERICAS, INC.; REGAL                    :
 CHEMICAL CO.; SCOTTS-SIERRA CROP                :
 PROTECTION CO.; AND SYNGENTA                    :
 CROP PROTECTION, INC.                           :
                                                 :
                                                 :
 APPEAL OF: BASF CORPORATION                     :


                      CONCURRING AND DISSENTING OPINION


JUSTICE BAER                                     DECIDED: JULY 21, 2020

       I join the majority opinion as to Issues One and Three, subject to the clarifications

set forth below. I likewise agree with the majority’s mandate, remanding the case to the

trial court to afford Appellants the opportunity to reassert their challenges to Appellee’s

expert scientific evidence pursuant to Frye v. United States, 293 F. 1013 (D.C. Cir. 1923).

I respectfully dissent, however, from Issue Two, as I agree that Appellee’s experts

engaged in improper extrapolation for the reasons ably set forth by the Chief Justice in

his dissenting opinion.




                          [J-92A-E-2019] [MO: Donohue, J.] - 4
       While I join the majority as to Issue One, I write separately to express my view that

this case involves closer questions as to whether the trial court abused its discretion,

given the analytical gaps identified by the trial court that call into question the methodology

employed by Appellee’s experts, as summarized by the Chief Justice, see id. at 6-10.

Indeed, some of these failings are also detailed in the majority’s recitation of the

Appellants’ experts’ testimony, see Majority Opinion, slip op. at 24-25.

       Nevertheless, I ultimately agree with the majority that the trial court abused its

discretion in concluding that Appellee’s experts’ testimonies were inadmissible under Frye

by utilizing its own assessment of the scientific evidence rather than specifically relying

upon Appellants’ experts’ analysis. While a case may involve such a blatant failure of an

expert to apply generally accepted methodologies that a trial court need not rely upon the

opposing party’s expert, trial courts in most cases should be guided by the experts offered

by the parties rather than determining scientific validity on their own, especially

considering the diversity of individual judges’ scientific knowledge. See Grady v. Frito-

Lay, Inc., 839 A.2d 1038, 1045 (Pa. 2003) (recognizing the need for “individual judges,

whose backgrounds in science may vary widely” to be “guided by the consensus that

exists in the scientific community”). Indeed, the risk of trial courts assuming the role of

scientific experts in determining what is “generally accepted” is more pronounced as the

science becomes more complex, as demonstrated by the case at bar. Accordingly, I

conclude that the trial court sub judice abused its discretion and remand is appropriate.

       I additionally write to distance myself respectfully from the majority opinion to the

extent it declines to recognize the trial court as “gatekeeper” in Frye challenges. Majority

Opinion, slip op. at 20.      As expressed by Judge Beck in Blum v. Merrell Dow

Pharmaceuticals, Inc., 705 A.2d 1314, 1325 (Pa. Super. 1997), aff’d, 764 A.2d 1 (Pa.

2000), “the gatekeeping role of the court, far from detracting from the jury’s function, is in




                           [J-92A-E-2019] [MO: Donohue, J.] - 5
fact essential to it [as it ensures] that what might appear to the jury to be science is not in

fact speculation in disguise.”

       Finally, I join Part II of the Chief Justice’s dissent, addressing this Court’s prior

decision in Betz v. Pneumo Abex LLC, 44 A.3d 27 (Pa. 2012).




                           [J-92A-E-2019] [MO: Donohue, J.] - 6
