                           NOT FOR PUBLICATION                           FILED
                    UNITED STATES COURT OF APPEALS                        JAN 22 2019
                                                                      MOLLY C. DWYER, CLERK
                                                                       U.S. COURT OF APPEALS
                           FOR THE NINTH CIRCUIT

ROBERT SEPE, Jr.,                               No.    17-16393

                Plaintiff-Appellant,            D.C. No.
                                                2:12-cv-01639-TLN-CKD
 v.

GORDON TRUCKING, INC. and                       MEMORANDUM*
ELWOOD HILL,

                Defendants-Appellees.

                   Appeal from the United States District Court
                      for the Eastern District of California
                    Troy L. Nunley, District Judge, Presiding

                    Argued and Submitted November 15, 2018
                            San Francisco, California

Before: FISHER and M. SMITH, Circuit Judges, and PIERSOL,** District Judge.

       Robert Sepe, Jr. (“Sepe”) appeals the district court’s order imposing

discovery sanctions under Rule 37(c)(1) of the Federal Rules of Civil Procedure

and order denying Sepe’s Federal Rules of Civil Procedure Rule 59(a) motion for a



      *
             This disposition is not appropriate for publication and is not precedent
except as provided by Ninth Circuit Rule 36-3.
      **
              The Honorable Lawrence L. Piersol, United States District Judge for
the District of South Dakota, sitting by designation.
new trial. We affirm.

      Sepe contends that the district court erred in limiting the causation testimony

of Dr. Orisek and Dr. Lemons in his case-in-chief under Rule 37(c)(1) to that of

treating physicians despite the district court’s finding that the failure to file expert

reports for these witnesses was harmless. Sepe argues that the district court’s error

caused him substantial prejudice, and that the district court abused its discretion in

denying his Rule 59(a) motion for a new trial. We have jurisdiction under 28

U.S.C. § 1291.

      We review both the district court's imposition of discovery sanctions and the

denial of the Rule 59(a) motion for abuse of discretion. Goodman v. Staples The

Office Superstore, LLC, 644 F.3d 817, 822 (9th Cir. 2011); Kode v. Carlson, 596

F.3d 608, 611 (9th Cir. 2010).

      Causation testimony by a treating physician is expert opinion, subject to the

disclosure and written report requirement detailed in Rule 26(a)(2) if the

physician’s opinion on causation was formed outside the course of treatment. See

Goodman v. Staples The Office Superstore, LLC, 644 F.3d 817, 826 (9th Cir. 2011)

(stating that a treating physician is only exempt from Rule 26(a)(2)(B)’s written

report requirement to the extent that his opinions were formed during the course of

treatment). Under Rule 37(c)(1), when a party fails to make the disclosures

required by Rule 26(a)(2), the party is not allowed to use the witness to supply


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expert testimony at trial unless it establishes that the failure to disclose was

substantially justified or harmless. See id. (citing Fed. R. Civ. P. 37(c)(1)).

        We hold that the district court erred in limiting the causation testimony of

Dr. Orisek and Dr. Lemons in Sepe’s case-in-chief to opinions formed during the

course of treatment. The district court held that Sepe’s failure to disclose the

physicians as experts and provide expert reports was harmless because the

defendants were aware of both witnesses and continued to subpoena their medical

records. Upon finding that the failure to disclose was harmless, discovery

sanctions under Rule 37(c)(1) limiting the testimony were not warranted.

      Although the district court erred in imposing discovery sanctions, we

conclude that the error was harmless. See Fed. R. Civ. P. 61 (stating the harmless

error rule). The district court subsequently permitted Sepe to recall Dr. Orisek to

give substantial expert testimony about causation. In addition, Sepe has not

identified any other causation evidence that Dr. Orisek and Dr. Lemons would

have presented absent the court’s order imposing discovery sanctions. Based on

the foregoing, the district court did not abuse its discretion by denying Sepe’s

motion for a new trial.

      AFFIRMED.




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