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You Might Not Need An Expert…But You Have To Show Something

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In a recent federal court case in Pennsylvania, a judge ruled that expert testimony is not always required to show that a product is defective – but a plaintiff is required to show enough non–expert evidence to permit a jury to reasonably reach that conclusion.  Block v. Gen. Motors LLC, No. CV 22-556, 2023 WL 8651376, at *1 (E.D. Pa. Dec. 14, 2023).  In that case, Derek Block, an automobile technician, injured his finger on a jagged piece of metal while replacing a batter on a GMC Yukon.  In his lawsuit, one of Block’s allegations was that GM “‘plac[ed] into the stream of commerce a defective’ metal bracing that caused his injury.”  Id.

GM moved for summary judgment, arguing in part that Block’s product liability claims failed because he did not produce expert testimony that the vehicle had a defect.  Block argued that Pennsylvania law did not require him to produce expert testimony to prove his claims – and even if it did, Block could serve as his own expert given his experience as an automobile technician.

The Court granted summary judgment in favor of GM on the products liability claims.  At the outset, the Court stated that from the claims, arguments and limited evidence that had been presented thus far, it appeared Mr. Block was pursuing a design or manufacturing defect claim.  The Court then distinguished when expert testimony is required in a case like this, and when it is not.  Expert testimony is required is the subject matter of a products liability claim is of a “highly technical nature.”  Id. at *3 (quoting  McCracken v. Ford Motor Co., 392 F. App'x 1, 3 (3d Cir. 2010)).  On the contrary, expert testimony is not required where “testimony and pictures may enable the jury to clearly see the construction of the [allegedly defective product] and the manner of its use.”  Id.  (quoting Padillas v. Stork-Gamco, Inc., 186 F.3d 412, 416 (3d Cir. 1999)).

The issue here was whether Block produced enough non-expert evidence for a jury to find in his favor.  The Court found that Block’s non-expert evidence, which consisted of his own deposition testimony and three photographs of the vehicle’s interior, was not sufficient to submit his claim to a jury.  Finally, the Court noted that Block could prove his claim without an expert – but – there was just not enough non-expert evidence.  This case reminds us of the importance of expert testimony in a products liability case – and in the alternative, provides an understanding of the extent of non-expert evidence a Plaintiff must show to prove their claim without the use of an expert.

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