Rene Junk brought this action in state court on behalf of her son, Tyler (T.J.) Junk, against Terminix International Company (Terminix), Dow Chemical Company and Dow AgroSciences LLC (collectively Dow), and Terminix employee Jim Breneman. Junk alleged that T.J.’s multiple medical conditions were caused by exposure to Dursban, an insecticide manufactured by Dow, distributed by Terminix, and applied to the Junk household by Breneman and other Terminix employees. *443 After Dow removed the case to federal district court, Junk moved to remand for lack of diversity since Junk and defendant Breneman were both citizens of Iowa. The district court denied the motion after concluding that Breneman had been fraudulently joined to evade diversity. Junk’s claims against Breneman were subsequently dismissed, and summary judgment was entered for Dow and Terminix. Junk appeals. We affirm the judgment in favor of Dow and Terminix but reverse in respect to the claim against Breneman.
I.
T.J. Junk was born two months premature with an enlarged heart and liver and tachycardia. It was also determined early in his life that T.J. had developmental delay and cerebral palsy. The Junks’ home had been infested with spiders during Rene Junk’s pregnancy, and she contacted Terminix about the problem. Terminix then sent out its employee Jim Breneman to consult with the family.
Five months before T.J.’s birth, Breneman enrolled the Junks in a Residential Pest Control Service Agreement. Breneman thereafter sprayed the pesticide Dursban inside and outside the Junks’ home. Junk alleges that she and her husband had informed Breneman that she was pregnant and had asked him about the safety of Dursban. Dursban contains the synthetic chemical chlorpyrifos. Breneman assured them that Dursban was a “naturally occurring organic material which would have no impact on human beings.” The Junks also allege that Breneman and other Terminix employees made similar representations before and after T.J.’s birth. Breneman and other Terminix employees made a total of twenty Dursban applications to the Junk household, the last occurring two years after T.J.’s birth.
On T.J.’s behalf Junk sued Terminix, Dow, and Breneman in Iowa state court. 1 Junk alleged that her exposure to Dursban during her pregnancy and T.J.’s exposure to the pesticide after his birth had caused T. J.’s severe neurological problems. Junk claimed breach of express and implied warranties, fraud, negligent misrepresentation, products liability, and negligence. The defendants filed a timely notice of removal to federal district court under 28 U. S.C. §§ 1441, 1446, claiming diversity jurisdiction under 28 U.S.C. § 1332(a).
Junk moved to remand the case to state court under 28 U.S.C. § 1447, arguing that the district court lacked diversity jurisdiction because defendant Breneman and T.J., the party in interest, were both citizens of Iowa. The defendants did not dispute Breneman’s Iowa citizenship, but argued that he had been fraudulently joined to defeat diversity jurisdiction. The district court denied Junk’s motion to remand the case to state court and her subsequent motions to reconsider. While Junk argued that T.J. had a colorable negligence claim against Breneman due to his false statements and other conduct, the court reasoned that Junk “could not maintain a cause of action ... under Iowa common law” because she had failed to allege explicitly that Breneman had deviated from Terminix’s instructions. The court later dismissed Junk’s claims against Breneman for failure to state a claim for the same reason.
Discovery continued after Breneman’s dismissal, and the district court made three subsequent pretrial evidentiary rulings which Junk contests on appeal. The court first excluded the testimony of Dr.
*444
Richard Fenske, one of Junk’s expert witnesses. Dr. Fenske is a professor at the University of Washington and an expert on human toxic exposure. The Junks retained him to determine whether T.J. had been exposed to an unsafe level of chlorpyrifos during his mother’s pregnancy and after his birth. Dr. Fenske testified that when making toxic exposure and dosage estimates in his research, he usually relies on a “deterministic modeling” method in which he creates an exposure model that accounts for numerous variables. In this case, however, he did not have sufficient data to perform such an analysis. Instead, he compared what he knew about the circumstances of T. J.’s exposure with those in published studies. This comparative analysis led him to conclude that T.J. had been exposed to an unsafe level of chlorpyrifos. Observing that Dr. Fenske had not followed his own usual methodology and concluding that he had relied on a number of ungrounded assumptions in his comparative approach, the district court excluded his opinion on the ground that his methodology was not sufficiently reliable.
See
Fed.R.Evid. 702;
Daubert v. Merrell Dow Pharm., Inc.,
Dr. Cynthia Bearer’s testimony was also excluded. She is a neonatologist and board certified pediatrician whom Junk retained to give her opinion on general and specific causation. She was asked whether chlorpyrifos could have caused the type of injuries that afflict T.J. and whether it did in fact cause them.
See Ranes v. Adams Labs., Inc.,
The district court also granted the defendants’ motion in limine to exclude an Environmental Protection Agency (EPA) report that summarized research on the effect of chlorpyrifos exposure on pregnant women, fetuses, and children. After examining a disclaimer on the report that appeared to east doubt on its trustworthiness, the court expressed concern that the report carried a risk of unfair prejudice and concluded that it was not admissible under Fed.R.Evid. 803(8)(C), 703, or 803(18).
Subsequent to those evidentiary rulings, the district court concluded that Junk could not raise a genuine issue of material fact on the issue of specific causation without Dr. Bearer’s opinion. On that basis the court granted summary judgment in favor of Dow and Terminix on all causes of action against them. Junk appeals, challenging the district court’s denial of her motion for remand and the subsequent dismissal of the claims against Breneman, the summary judgment for Dow and Terminix, and the orders excluding Junk’s experts and the EPA report.
II.
We review the court’s denial of remand de novo.
In re Prempro Prods. Liab. Litig.,
Subject matter jurisdiction asserted under 28 U.S.C. § 1332 may be maintained only where there is complete diversity, that is “where no defendant holds citizenship in the same state where any plaintiff holds citizenship.”
Prempro,
The parties dispute whether we should review the district court’s denial of Junk’s remand motion and subsequent dismissal of Breneman under the fraudulent joinder standard outlined in
Filla v. Norfolk Southern Railway Co.,
Junk argues that the
Filia
standard is the proper test to decide whether a remand to state court was appropriate and whether the court’s subsequent dismissal of Breneman was proper. This was the approach we followed in
Wilkinson v. Shackelford,
We do not consider
Simpson’s
holding to be as broad as appellees suggest. In
Simpson
a nondiverse defendant opposed remand to state court since he was immune from suit under a state workers compensation law.
In
Wilkinson,
a case decided before
Simpson,
we faced facts similar to those present here. The district court decided there that a nondiverse defendant had been fraudulently joined by the plaintiff to defeat diversity jurisdiction. The court therefore denied the plaintiffs motion to remand and granted the nondiverse defendant’s motion for dismissal.
Wilkinson,
We took a similar approach in
Menz v. New Holland North America, Inc.,
A comparison of these decisions shows no direct conflict between
Simpson
and
Wilkinson. Simpson
involved a nondiverse defendant who had been fraudulently joined since he claimed immunity under a state workers compensation law. Neither
Wilkinson
nor the case before the court have such an immunity issue. Moreover, even if there had been a conflict between
Wilkinson
and
Simpson,
“the better practice normally [would be] to follow the earliest opinion, as it should have controlled the subsequent panels that created the conflict.”
United States v. Robertson,
Joinder is not fraudulent where “there is arguably a reasonable basis for predicting that the state law might impose liability based upon the facts involved.”
Filia,
An employee may be held liable under Iowa law for on the job negligence.
Hartig v. Francois,
Although Junk’s complaint was not as artful as it might have been, we conclude that it stated facts sufficient to make a colorable claim against Breneman under Iowa law. Junk alleged that Breneman “made representations to [the Junks] that Dursban was a naturally occurring organic material which would have no impact on human beings.” In the section of
*447
Junk’s complaint alleging negligence, Junk alleged that Terminix and Breneman “[failed] to warn ... of health risks associated with the use of [Dursban]” and did “not requir[e] consumers to vacate their house when Dursban was sprayed.” Although the conjunctive nature of Junk’s complaint did not always distinguish between allegations against Terminix, the employer, and Breneman, the employee, “all doubts ... should be resolved in favor of remand.”
Prempro,
We conclude that there was “arguably a reasonable basis for predicting that the state law might impose liability based upon the facts involved.”
Filia,
III.
After the district court denied the motion for remand on April 3 and dismissed Breneman on October 3, 2006, the litigation proceeded against the corporate defendants throughout 2007 and 2008. During that time the court issued orders excluding evidence and it granted summary judgment in November 2008 in favor of Dow and Terminix on all remaining claims. Junk urges that the erroneous denial of remand should void the court’s subsequent rulings in favor of Dow and Terminix, but “a district court’s error in failing to remand a case improperly removed is not fatal to the ensuing adjudication if federal jurisdictional requirements are met at the time judgment is entered.”
Caterpillar Inc. v. Lewis,
Because the district court’s summary judgment order turned on disputed evidentiary rulings, we address those rulings first. We reverse a trial court’s decision on the admissibility of expert evidence only on the basis of a clear and prejudicial abuse of discretion.
Barrett v. Rhodia, Inc.,
If scientific, technical, or other specialized knowledge will assist the trier of fact to understand the evidence or to determine a fact in issue, a witness qualified as an expert by knowledge, skill, experience, training, or education may testify thereto in the form of an opinion *448 or otherwise, if (1) the testimony is based on sufficient facts or data, (2) the testimony is the product of reliable principles and methods, and (3) the witness has applied the principles and methods reliably to the facts of the case.
In order to be admissible scientific testimony must be “both reliable and relevant.”
Barrett,
To be deemed reliable, the methodology underlying an expert’s conclusions must be “scientifically valid.” Id Speculative testimony should not be admitted.
Concord Boat Corp. v. Brunswick Corp.,
Dr. Richard Fenske was retained by Junk to offer his opinion on T.J.’s exposure to chlorpyrifos during his mother’s pregnancy and after his birth. Dr. Fenske’s academic experience and expertise are not in dispute. The district court concluded, however, that Dr. Fenske’s methodological approach in this particular case was not sufficiently reliable. Dr. Fenske testified that he generally employs a deterministic modeling approach to estimate toxic exposure levels. Since he lacked the data necessary to conduct such an analysis here, he could not estimate exposure levels as he normally does. Instead he resorted to a comparative analysis, analogizing to previous studies of household chlorpyrifos exposure before ultimately concluding that T.J. had been exposed to an unsafe level of the chemical.
The district court identified several grounds for its decision that Dr. Fenske’s opinion was not sufficiently reliable: Dr. Fenske admitted that he had been unable to follow the modeling methods that he uses in his published research and teaching because he lacked necessary data. In this case he used a comparative method instead, comparing the circumstances the Junks experienced to several studies which had measured the effects of chlorpyrifos exposure.
The court concluded that Dr. Fenske’s comparative analysis depended on unsupported assumptions. He did not account for differences between conditions in the Junk household and those described in the articles he consulted. In one instance his only basis for comparison was the fact that the Junk household and those in a particular study were all treated with chlorpyrifos. In another he relied on a study where the only common variable between the Junks’ experience, and the homes studied was the total amount of chlorpyrifos applied. Dr. Fenske disregarded other important variables such as where and how chlorpyrifos was applied in the household and whether the homes in a comparison study were the same size as the Junks’ home.
While Junk correctly notes that Dr. Fenske was not required to produce “a mathematically precise table equating levels of exposure with levels of harm,”
Wright v. Willamette Indus., Inc.,
Junk also appeals the district court’s exclusion of Dr. Bearer’s expert opinion on specific causation. Her opinion was based on her differential diagnosis of the cause of T.J.’s neurological condition. Although the court initially planned to receive it, the court indicated that her “expert causation opinion [would] be reexamined ... when the admissibility of the expert testimony of Dr. Fenske [came] before the Court” since she had relied on his conclusions. After the district court addressed Dr. Fenske’s opinion on exposure levels and found it wanting, it revisited Dr. Bearer’s testimony and excluded her opinion on specific causation.
Because Dr. Bearer’s differential diagnosis depended on Dr. Fenske’s opinion on exposure, the district court did not abuse its discretion in excluding it. A differential diagnosis begins with an expert’s “ruling in” plausible causes of an injury.
See Kudabeck v. Kroger Co.,
Junk further appeals the district court’s order excluding an EPA report she had offered. The report summarized the findings of various studies. Junk argues that the report was admissible either under Rule 803(8)(C) or as data relied upon by an expert under Rule 703. We conclude that the district court correctly determined that the exceptions provided by those rules do not apply to this report. Rule 803(8)(C) provides an exception to the hearsay rule permitting admission of “factual findings resulting from an investigation made pursuant to authority granted by law ... unless the sources of information or other circumstances indicate a lack of trustworthiness.”
While the parties contest whether the EPA report was “made pursuant to authority granted by law,” we need not reach that issue. To be admissible under Rule 803(8)(C), “EPA reports must survive a trustworthiness inquiry.”
O’Dell v. Hercules, Inc.,
Junk’s argument that the EPA report is admissible through Dr. Bearer’s expert testimony under Rule 703 also fails. Rule 703 provides that “[fjacts or data that are otherwise inadmissible shall not be disclosed to the jury by the proponent of the opinion ... unless the court determines that their probative value in assisting the jury to evaluate the expert’s opinion substantially outweighs their prejudicial effect.” Because the report takes the form of a brief summary of research rather than a scholarly publication, the court could determine that it had little probative value. The district court also concluded that the report’s unfair prejudicial effect could be substantial if the jury were misled “into believing that [the] report records findings by the EPA.” Because we agree that the report’s probative value was minimal and its prejudicial potential substantial, we conclude that the district court did not abuse its discretion in excluding it.
IV.
After making its evidentiary rulings, the district court entered an order granting summary judgment to Dow and Terminix on all claims. Junk appeals from that judgment. “We review a grant of summary judgment de novo, affirming if the record shows that there is no genuine issue of material fact and the prevailing party is entitled to judgment as a matter of law.”
Barrett,
To prevail in a toxic tort case such as this, the plaintiff must show both general and specific causation.
Ranes,
Junk’s only expert witness on specific causation, Dr. Bearer, did not survive the district court’s Dauberb analysis. After the court properly excluded Dr. Bearer’s testimony, Junk could not prove specific causation as required under Iowa law. As there was no longer a genuine issue of material fact as to that necessary element, Dow and Terminix were entitled to judgment as a matter of law and the court properly granted summary judgment.
Finally, Junk argues that the district court violated her Seventh Amendment right to a jury trial by improperly weighing evidence in the course of its
Dauberb
rulings. As already discussed, we conclude that the court did not abuse its discretion in excluding unreliable expert testimony. Junk does not cite any case for the notion that a proper
Dauberb
ruling violates a party’s right to a jury trial. Nor does a grant of summary judgment violate a party’s right to a jury trial where, as here, the moving party is entitled to judgment as a matter of law.
See Harris v. Interstate Brands Corp.,
V.
For these reasons we affirm the summary judgment in favor of Dow and Ter *451 minix, but reverse the order dismissing Junk’s claim against Breneman and return that claim to the district court with instructions to remand it to state court.
Notes
. Two other defendants, Harold Obrecht and Sureco, Inc., were voluntarily dismissed upon Junk’s motion and are not subjects of this appeal.
. We note that the
Wilkinson
approach also comports with the practice of other circuits which have reviewed cases in which a district court found a nondiverse defendant fraudulently joined and subsequently dismissed the claims against it. Such cases have applied a fraudulent joinder standard similar to that in
Filia. See e.g., Henderson v. Washington Nat’l Ins. Co.,
. Evidence arose during discovery tending to support this reading of the complaint. It was learned that Terminix had a "sensitive situations” policy which instructed employees about appropriate statements to make to customers and special procedures for treatment of homes where there were pregnant women. Breneman's alleged statements and conduct would appear to have violated this policy. This evidence was not discovered until after the court concluded that Breneman had been fraudulently joined and dismissed the claims against him, but in any event it is not necessary for resolution of the fraudulent joinder issue.
. Junk also challenges the district court's decision to exclude the specific causation testimony of another expert, Dr. Mohamed Abou-Donia. The district court excluded that testimony on that same ground that it excluded Dr. Bearer’s testimony: Dr. Abou-Donia had no scientifically valid basis for assuming that Rene and T.J. Junk were exposed to unsafe chlorpyrifos levels. For the reasons discussed above, the district court did not abuse its discretion in excluding Dr. Abou-Donia's testimony on specific causation.
