Proof and Defense of Causation in Failure-to-Warn Claims

Failure-to-warn is alleged in nearly every product liability lawsuit. Often, the claim is added to an action based primarily on defective design or manufacture. Occasionally, failure-to-warn will be the only claim. The failure-to-warn claim is frequently dismissed by the plaintiff or the court before or during trial.

In litigating failure-to-warn claims, the focus often is on duty (whether the manufacturer should have included a warning) and adequacy issues. In most cases, there is little attention paid to proof that the lack of a warning, or an inadequate warning, caused the accident. This article focuses on strategies for proving and defending the causation element of failure-to-warn.

Causation

Proof or defense of causation varies, depending on the nature of the failure-to-warn claim. In some cases, the plaintiff will allege that the product lacked a warning. In others, the claim will be that the product included a warning, but it was inadequate because it lacked critical information about the risk. Plaintiffs may also allege that a warning was not conspicuous enough to catch the user's attention. Also, the purpose of warnings may be different; some warnings “reduce the risk of product-related injury by allowing consumers to behave more carefully” and others allow consumers to make informed choices. Henderson & Twerski, Doctrinal Collapse in Products Liability: The Empty Shell of Failure-to-Warn,” 65 N.Y.U. L. Rev. 265, 285 (1990).

Proof and defense of causation also depends on who the plaintiff alleges would have responded to an adequate warning. In many cases, that is the injured plaintiff, who is also the product user. Sometimes, the warning recipient is a third party who is using the product, such as a co-worker. The intended audience for a warning may also be a professional, such as a physician, who is advising or making choices for the plaintiff.

Simply proving that a defendant has breached a duty to warn is not enough. The plaintiff must also prove that the breach caused his harm. See U.S. Xpress, Inc. v. Great N. Ins. Co., No. 01-0195, 2003 WL 124021, at *5 (D. Minn. Jan. 8, 2003) (holding that the defendant had a duty to warn, the defendant failed to warn adequately, and that failure caused the accident). But proving causation is challenging because a plaintiff must prove a hypothetical: that the product user would have acted differently had the manufacturer provided an adequate warning.

Courts take one of three approaches to causal proof: 1) an objective standard (plaintiff must prove an adequate warning would have prevented harm to the reasonable person); 2) a subjective standard (requiring proof that an adequate warning would have prevented harm to the plaintiff); and 3) the “read and heed” presumption. Geistfeld, Inadequate Product Warnings and Causation, 30 U. Mich. J. L. Ref. 309, 337-38 (1997).

Plaintiff's Proof of Causation

Rely on the Heeding Presumption. The “read and heed” presumption (heeding presumption) is a rebuttable presumption that the product user would have read and followed an adequate warning. The presumption arose from a mix of public policy considerations about product safety, concern about the difficulty of proving causation in failure-to-warn cases, and, arguably, support for such a presumption in the Restatement (Second) of Torts section 402A, comment j (“[w]here warning is given, the seller may reasonably assume that it will be read and heeded”). Coffman v. Keen Corp. , 628 A.2d 710 (N.J. 1993) (adopting the presumption based on the above criteria and oting other jurisdictions have done the same); Jones, Annotation, Presumption or Inference, in Products Liability Action Based on Failure-to-Warn, That User Would Have Heeded an Adequate Warning Had One Been Given, 38 A.L.R. 5th 683, 701-04 (2002) (discussing states that have adopted the presumption).

The heeding presumption essentially eliminates the plaintiff's burden of proving causation in his prima facie case. The burden then falls on the defendant to rebut the presumption. Bloxom v. Bloxom, 512 So. 2d 839, 850 (La. 1987) (“The presumption, may, however, be rebutted if the manufacturer produces contrary evidence which persuades the trier of fact that an adequate warning or instruction would have been futile under the circumstances.”). If the defendant is unable to produce evidence to rebut the presumption, the plaintiff should prevail on that issue as a matter of law. If, however, the defendant satisfies its burden of production, the heeding presumption disappears and the plaintiff must prove by a preponderance of evidence that the failure-to-warn was a proximate cause of his injury. Sharpe v. Bestop, Inc., 713 A.2d 1079 (N.J. Super. Ct. App. Div. 1998).

Some courts, however, have rejected the heeding presumption. In Rivera v. Philip Morris, 209 P.3d 271 (Nev. 2009), the court reasoned that it is not logical to presume that a plaintiff would have heeded an adequate warning, if provided. “[W]arnings are everywhere in the modern world and often go unread or, where read, ignored.” Id. at 277.

In light of these concerns, a plaintiff should not rely on the heeding presumption and must consider how he will prove causation. Such proof will vary from case to case. Generally, a plaintiff must establish that he (or the product user if different) was not aware of the danger, and would have read and heeded the proposed warning, thus changing his behavior to avoid the injury.

Establish That Plaintiff Was Not Aware of the Danger. The plaintiff must establish that he had no prior knowledge of the danger, because a failure-to-warn cannot be the cause of harm when the product user was already aware of the danger. Krajewski v. Enderes Tool Co., Inc , 469 F.3d 705 (8th Cir. 2006) (failure-to-warn was not causal where plaintiff was aware that using a pry bar without goggles could cause eye injury). So consider whether the danger was well known or obvious before making a failure-to-warn claim: such a claim concerning a sharp knife or a heavy hammer is bound to fail. Also consider whether the user was sophisticated enough that he might be expected to know of a product's risk absent a warning.

Establish That the Plaintiff Read and Relied Upon the Defective Warning. When a plaintiff claims a warning is inadequate, he must establish that he read and relied on the warning. A plaintiff's failure to read the existing warning defeats the causal link between the inadequate warning and the harm. Bishop v. Bombardier, Inc., 399 F.Supp. 2d 1372 (M.D. Ga. 2005) (in a personal watercraft case, the plaintiff could not recover because he could not prove he read existing warnings or recall what they said, thus a more specific warning would not have altered his actions and prevented his injury). The exception is if the plaintiff is challenging the conspicuity of the original warning: The existing warning was too small or in the wrong location, and thus the plaintiff was unable to read it.

Establish That the Plaintiff Would Have Acted Differently Had There Been an Adequate Warning. The Restatement (Third) of Torts: Products Liability ' 2 cmt. i (1997), provides that:

[n]otwithstanding the defective condition of the product in the absence of adequate warnings, if a particular user or consumer would have decided to use or consume even if warned, the lack of warnings is not a legal cause of that plaintiff's harm.

A plaintiff must prove that he would not have accepted the risk if properly warned. Austin v. Will-Burt Co., 361 F.3d 862 (5th Cir. 2004) (a manufacturer's failure-to-warn is not a proximate cause of injury absent evidence that an adequate warning would have changed the product user's conduct); Holowaty v. McDonald's Corp., 10 F.Supp.2d 1078 (D. Minn. 1998) (to prove causation, plaintiffs need to show that they would have acted differently if they had been warned of the risk). Proving this element poses significant challenges for plaintiffs.

Present Plaintiff's Testimony That He Would Have Read and Heeded the Warning. A plaintiff can claim he would have heeded an adequate warning, and acted to avoid the risk. But in some jurisdictions, such a self-serving statement is not admissible. Magoffe v. JLG Indus, 375 Fed Appx. 848 (10th Cir. 2010) (holding that Fed. R. Evid. ' 701 does not permit a lay witness to speculate about whether he would have followed a hypothetical warning or what the hypothetical effect would be). However, there are paths around this hurdle. Consider whether the plaintiff can establish that he is safety-conscious or has habitually followed similar warnings. For example, a plaintiff with a severe allergy is likely to have followed an appropriate warning on a product containing the allergen.

Present Expert Testimony That Adequate Warning Would Have Been Effective. In most jurisdictions, a plaintiff does not have to present an alternative warning, but can argue that some unspecified “better” warning would have prevented his harm. Twerski & Henderson, “Fixing Failure-to-Warn,” Brooklyn Law School, Legal Studies Paper No. 301, 90 Ind. L. J . (2014 Forthcoming) at 14. But if the court so requires or if the defendant has rebutted the heeding presumption, the plaintiff may have to present an alternative warning. Fortunately, warnings are not developed in a vacuum. There are experts who can testify, based on psychological, physiological, and other data, that the defendant's warning was ineffective and, conversely, the plaintiff's alternative warning would be more effective.

A well-credentialed expert may be able to identify flaws in the defendant's warning's size, location, design and wording, and the existence of any better warnings on competitor products. Particularly in those jurisdictions that follow an objective standard of causation (requiring a plaintiff to prove an adequate warning would have prevented harm to the reasonable person), an expert should be able, through testing the efficacy of both the original and proposed warnings, to provide testimony that bolsters the plaintiff's causation argument.

Defense of Causation Claims

Causation is often overlooked by the plaintiff and the court; defense counsel should highlight the issue. The defense strategy must start early in discovery, especially in depositions of the plaintiff or other product user. The defense also may choose experts and develop expert opinions to address causation.

Demand That the Plaintiff Offer a Reasonable Alternative Warning. The Reporters for the Restatement (Third) of Torts: Products Liability, recently argued that just as plaintiffs in a design defect case are required to offer a reasonable alternative design, plaintiffs in a failure-to-warn case should be required to submit a reasonable alternative warning (“identify specifically what, how, and to whom the defendant distributor should have communicated additional risk information”). Twerski & Henderson, Fixing Failure-to-Warn, 90 Ind. L. J. at 10. They contend that “a defendant cannot challenge ' whether [a warning] would have saved the plaintiff from injury without knowing the specifics of the proposed warning.” Id. at 24. The defense lawyer should persuade the court to require the plaintiff to detail the warning he contends should have been given. Regardless, the defense should pin down the plaintiff and his expert on specifics of their warning claim.

Police Admissibility of Plaintiff's Proof. In some courts, the plaintiff's testimony that he or she would have read and heeded a warning is too speculative to be admitted. See Magoffe, 375 Fed Appx. 848. Expert testimony on causation issues, e.g., an untested warning would have prevented the accident, may be unreliable under Rule 702 or its equivalents. Defense counsel should move to exclude speculative and unreliable testimony.

Prove Product User's Awareness of Risk. Plaintiff's prior awareness of the risk will defeat causation. If the plaintiff knows the risk, a warning would not have changed his conduct. See Ramstad v. Lear Siegler Diversified Holdings Corp. , 836 F.Supp. 1511 (D. Minn. 1993) (failure-to-warn claim dismissed when plaintiff was aware of danger presented by grain auger intake).

Proving the product user's knowledge is an effective strategy in cases involving a sophisticated user who helps the plaintiff make decisions on product use. For example, the knowledge level of the plaintiff's treating physician who prescribes a medical device or pharmaceutical must be explored. If the physician is already aware of the harm that allegedly should have been addressed by a different warning, then the existing warning did not factor in the physician's choice of the device or drug, or in providing informed consent to the patient/plaintiff. Ackermann v. Wyeth Pharms., 526 F.3d 203 (5th Cir. 2008) (physician aware of suicide risk and would have prescribed drug even if different warning provided).

Prove Product User Did Not Read the Warning. Lack of, or inadequacy of, a warning is not causal if the product user did not read the warnings accompanying the product. If the defendant can prove that the user did not read the product's warnings, the failure-to-warn claim should be dismissed. Motus v. Pfizer, 358 F.3d 659 (9th Cir. 2003) (inadequate warning claim dismissed when prescribing physician did not read warnings before prescribing drug).

This approach may not work if the plaintiff claims that he did not read the warning because it was not conspicuous enough, e.g. , was not of a proper color or size, or was buried in the manual. See Bowbeer, et al., Warning: Failure to Read This Article May Be Hazardous to Your Failure-to-Warn Defense, 27 Wm. Mitchell L. Rev. 439, 460 (2000) (“[F]ailure to read the warning because the warning was not noticed in the first instance can raise the issue of the warning's adequacy, a question of fact, which may preclude judgment as a matter of law.”).

Similarly, if the product user admits he habitually does not read warnings, then failure-to-warn cannot have caused the accident. Even if an adequate warning appeared on the product, the plaintiff cannot prove he would have read and heeded it.

Prove Product User Does Not Heed Warnings. Even if the plaintiff shows that the user read the product's warnings, evidence that the user frequently disregards warnings may defeat causation. Evidence that the plaintiff smokes, drinks while pregnant, or does not use seat belts, despite relevant warnings, will help prove that he or she would not have heeded the proffered safety messages. The court may require the defendant's evidence of disregard of warnings to be related to use of the product involved in the accident, and to reach the level of habit, rather than anecdotal character evidence, to be admissible on causation. See, e.g., Sharpe v. Bestop, Inc. , 730 A.2d 285, 286 (N.J. 1999) (“habitual disregard” of seat belt warning admissible, hile “occasional disregard of warnings not to drink and drive” not admissible).

Offer Expert Testimony That Proposed Warning Would Not Have Affected Conduct. Defense experts may offer opinions that the plaintiff's proposed warning's effectiveness is untested or questionable. Communications or industrial psychology experts may also explain that the product user was habituated to using the product and a warning would not have affected his conduct. See Martin, et al., 'If Only I Would Have Been Told ” A Failure-to-Warn Discussion: Causation, the Uncertainty Principle, and the Benign Experience Principle,” 40 Product Safety & Liability Reporter 879 (2012).

Explore Other Evidence to Defeat Causation. Each case presents unique facts, which should be explored for causation defenses. For example, lack of warning may not be the cause of the accident if the plaintiff learned to use the product by earlier, frequent use of a similar product made by another manufacturer. Or a warning may be irrelevant when the plaintiff must make a split-second decision about product use. Or the plaintiff may not be able to prove that the manufacturer could have delivered an effective warning to the user. See, e.g., Huitt v. Southern California Gas Co., 188 Cal. App.4th 1586 (Cal. App. 2010) (plaintiff failed to prove that warning by natural gas supply company that odorant could be adsorbed by new steel pipes would have reached plaintiff).

Rebut the Read and Heed Presumption. The same evidence offered to defeat causation may burst the heeding presumption, requiring the plaintiff to offer evidence that an adequate warning would have been read and heeded to get his claim to the jury. Evidence that the user was aware of the harm and confronted it anyway, or did not read the product labels, or does not customarily read warnings may defeat the presumption. See Bowbeer, Warning: Failure to Read This Article ' , 27 Wm. Mitchell L. Rev. at 462-63.

Move for Summary Judgment or to Dismiss When Undisputed Facts Defeat Causation . If the defense develops undisputed evidence defeating causation, e.g., the plaintiff was aware of the risk or did not read the challenged warning, it should seek dismissal of the failure-to-warn claims at summary judgment or at trial before submission to the jury. If the record is fully developed, the defendant may win summary judgment when there is no evidence to support causation. Koken v. Black & Veatch Constr., Inc., 426 F.3d 39, 49 (1st Cir. 2005) (summary judgment appropriate where plaintiff failed to offer proof that “foreman would have ordered a course of action different from that which occurred” if he had received a warning).

Move to Dismiss When Plaintiff Fails to Prove Causation. In a state that has not adopted the heeding presumption, or if the presumption is rebutted, the plaintiff's failure to offer evidence at trial that the product user would have read an adequate warning and changed his conduct to avoid the risk should result in dismissal of the failure-to-warn claim. At the conclusion of the plaintiff's case, defense counsel should make a Rule 50 motion for judgment as a matter of law. See, e.g., Huitt, 188 Cal. App.4th at 1589 (trial court should have dismissed failure-to-warn claim when “there was no evidence that, had the [defendant] issued a warning, [plaintiffs] would have been aware of it”).

Conclusion

While duty and adequacy issues may predominate in failure-to-warn litigation, the causation issue is equally important and may be more challenging. Even if they pursue the claim in a state with a heeding presumption, plaintiffs' lawyers must prepare a strategy to prove that absence of an adequate warning caused plaintiff's loss. Defense counsel must plan to defeat causation at all stages of discovery and trial. The failure-to-warn claim is more likely to be resolved justly with proper focus by the parties and the court.

George W. Soule , a member of this newsletter's Board of Editors, is Partner at Soule & Stull LLC in Minneapolis. Kevin P. Curry is Counsel at the firm.

Failure-to-warn is alleged in nearly every product liability lawsuit. Often, the claim is added to an action based primarily on defective design or manufacture. Occasionally, failure-to-warn will be the only claim. The failure-to-warn claim is frequently dismissed by the plaintiff or the court before or during trial.

In litigating failure-to-warn claims, the focus often is on duty (whether the manufacturer should have included a warning) and adequacy issues. In most cases, there is little attention paid to proof that the lack of a warning, or an inadequate warning, caused the accident. This article focuses on strategies for proving and defending the causation element of failure-to-warn.

Causation

Proof or defense of causation varies, depending on the nature of the failure-to-warn claim. In some cases, the plaintiff will allege that the product lacked a warning. In others, the claim will be that the product included a warning, but it was inadequate because it lacked critical information about the risk. Plaintiffs may also allege that a warning was not conspicuous enough to catch the user's attention. Also, the purpose of warnings may be different; some warnings “reduce the risk of product-related injury by allowing consumers to behave more carefully” and others allow consumers to make informed choices. Henderson & Twerski, Doctrinal Collapse in Products Liability: The Empty Shell of Failure-to-Warn,” 65 N.Y.U. L. Rev. 265, 285 (1990).

Proof and defense of causation also depends on who the plaintiff alleges would have responded to an adequate warning. In many cases, that is the injured plaintiff, who is also the product user. Sometimes, the warning recipient is a third party who is using the product, such as a co-worker. The intended audience for a warning may also be a professional, such as a physician, who is advising or making choices for the plaintiff.

Simply proving that a defendant has breached a duty to warn is not enough. The plaintiff must also prove that the breach caused his harm. See U.S. Xpress, Inc. v. Great N. Ins. Co., No. 01-0195, 2003 WL 124021, at *5 (D. Minn. Jan. 8, 2003) (holding that the defendant had a duty to warn, the defendant failed to warn adequately, and that failure caused the accident). But proving causation is challenging because a plaintiff must prove a hypothetical: that the product user would have acted differently had the manufacturer provided an adequate warning.

Courts take one of three approaches to causal proof: 1) an objective standard (plaintiff must prove an adequate warning would have prevented harm to the reasonable person); 2) a subjective standard (requiring proof that an adequate warning would have prevented harm to the plaintiff); and 3) the “read and heed” presumption. Geistfeld, Inadequate Product Warnings and Causation, 30 U. Mich. J. L. Ref. 309, 337-38 (1997).

Plaintiff's Proof of Causation

Rely on the Heeding Presumption. The “read and heed” presumption (heeding presumption) is a rebuttable presumption that the product user would have read and followed an adequate warning. The presumption arose from a mix of public policy considerations about product safety, concern about the difficulty of proving causation in failure-to-warn cases, and, arguably, support for such a presumption in the Restatement (Second) of Torts section 402A, comment j (“[w]here warning is given, the seller may reasonably assume that it will be read and heeded”). Coffman v. Keen Corp. , 628 A.2d 710 (N.J. 1993) (adopting the presumption based on the above criteria and oting other jurisdictions have done the same); Jones, Annotation, Presumption or Inference, in Products Liability Action Based on Failure-to-Warn, That User Would Have Heeded an Adequate Warning Had One Been Given, 38 A.L.R. 5th 683, 701-04 (2002) (discussing states that have adopted the presumption).

The heeding presumption essentially eliminates the plaintiff's burden of proving causation in his prima facie case. The burden then falls on the defendant to rebut the presumption. Bloxom v. Bloxom , 512 So. 2d 839, 850 (La. 1987) (“The presumption, may, however, be rebutted if the manufacturer produces contrary evidence which persuades the trier of fact that an adequate warning or instruction would have been futile under the circumstances.”). If the defendant is unable to produce evidence to rebut the presumption, the plaintiff should prevail on that issue as a matter of law. If, however, the defendant satisfies its burden of production, the heeding presumption disappears and the plaintiff must prove by a preponderance of evidence that the failure-to-warn was a proximate cause of his injury. Sharpe v. Bestop, Inc. , 713 A.2d 1079 (N.J. Super. Ct. App. Div. 1998).

Some courts, however, have rejected the heeding presumption. In Rivera v. Philip Morris , 209 P.3d 271 (Nev. 2009), the court reasoned that it is not logical to presume that a plaintiff would have heeded an adequate warning, if provided. “[W]arnings are everywhere in the modern world and often go unread or, where read, ignored.” Id . at 277.

In light of these concerns, a plaintiff should not rely on the heeding presumption and must consider how he will prove causation. Such proof will vary from case to case. Generally, a plaintiff must establish that he (or the product user if different) was not aware of the danger, and would have read and heeded the proposed warning, thus changing his behavior to avoid the injury.

Establish That Plaintiff Was Not Aware of the Danger. The plaintiff must establish that he had no prior knowledge of the danger, because a failure-to-warn cannot be the cause of harm when the product user was already aware of the danger. Krajewski v. Enderes Tool Co., Inc , 469 F.3d 705 (8th Cir. 2006) (failure-to-warn was not causal where plaintiff was aware that using a pry bar without goggles could cause eye injury). So consider whether the danger was well known or obvious before making a failure-to-warn claim: such a claim concerning a sharp knife or a heavy hammer is bound to fail. Also consider whether the user was sophisticated enough that he might be expected to know of a product's risk absent a warning.

Establish That the Plaintiff Read and Relied Upon the Defective Warning. When a plaintiff claims a warning is inadequate, he must establish that he read and relied on the warning. A plaintiff's failure to read the existing warning defeats the causal link between the inadequate warning and the harm. Bishop v. Bombardier, Inc. , 399 F.Supp. 2d 1372 (M.D. Ga. 2005) (in a personal watercraft case, the plaintiff could not recover because he could not prove he read existing warnings or recall what they said, thus a more specific warning would not have altered his actions and prevented his injury). The exception is if the plaintiff is challenging the conspicuity of the original warning: The existing warning was too small or in the wrong location, and thus the plaintiff was unable to read it.

Establish That the Plaintiff Would Have Acted Differently Had There Been an Adequate Warning. The Restatement (Third) of Torts: Products Liability ' 2 cmt. i (1997), provides that:

[n]otwithstanding the defective condition of the product in the absence of adequate warnings, if a particular user or consumer would have decided to use or consume even if warned, the lack of warnings is not a legal cause of that plaintiff's harm.

A plaintiff must prove that he would not have accepted the risk if properly warned. Austin v. Will-Burt Co. , 361 F.3d 862 (5th Cir. 2004) (a manufacturer's failure-to-warn is not a proximate cause of injury absent evidence that an adequate warning would have changed the product user's conduct); Holowaty v. McDonald's Corp. , 10 F.Supp.2d 1078 (D. Minn. 1998) (to prove causation, plaintiffs need to show that they would have acted differently if they had been warned of the risk). Proving this element poses significant challenges for plaintiffs.

Present Plaintiff's Testimony That He Would Have Read and Heeded the Warning. A plaintiff can claim he would have heeded an adequate warning, and acted to avoid the risk. But in some jurisdictions, such a self-serving statement is not admissible. Magoffe v. JLG Indus, 375 Fed Appx. 848 (10th Cir. 2010) (holding that Fed. R. Evid. ' 701 does not permit a lay witness to speculate about whether he would have followed a hypothetical warning or what the hypothetical effect would be). However, there are paths around this hurdle. Consider whether the plaintiff can establish that he is safety-conscious or has habitually followed similar warnings. For example, a plaintiff with a severe allergy is likely to have followed an appropriate warning on a product containing the allergen.

Present Expert Testimony That Adequate Warning Would Have Been Effective. In most jurisdictions, a plaintiff does not have to present an alternative warning, but can argue that some unspecified “better” warning would have prevented his harm. Twerski & Henderson, “Fixing Failure-to-Warn,” Brooklyn Law School, Legal Studies Paper No. 301, 90 Ind. L. J . (2014 Forthcoming) at 14. But if the court so requires or if the defendant has rebutted the heeding presumption, the plaintiff may have to present an alternative warning. Fortunately, warnings are not developed in a vacuum. There are experts who can testify, based on psychological, physiological, and other data, that the defendant's warning was ineffective and, conversely, the plaintiff's alternative warning would be more effective.

A well-credentialed expert may be able to identify flaws in the defendant's warning's size, location, design and wording, and the existence of any better warnings on competitor products. Particularly in those jurisdictions that follow an objective standard of causation (requiring a plaintiff to prove an adequate warning would have prevented harm to the reasonable person), an expert should be able, through testing the efficacy of both the original and proposed warnings, to provide testimony that bolsters the plaintiff's causation argument.

Defense of Causation Claims

Causation is often overlooked by the plaintiff and the court; defense counsel should highlight the issue. The defense strategy must start early in discovery, especially in depositions of the plaintiff or other product user. The defense also may choose experts and develop expert opinions to address causation.

Demand That the Plaintiff Offer a Reasonable Alternative Warning. The Reporters for the Restatement (Third) of Torts: Products Liability, recently argued that just as plaintiffs in a design defect case are required to offer a reasonable alternative design, plaintiffs in a failure-to-warn case should be required to submit a reasonable alternative warning (“identify specifically what, how, and to whom the defendant distributor should have communicated additional risk information”). Twerski & Henderson, Fixing Failure-to-Warn, 90 Ind. L. J. at 10. They contend that “a defendant cannot challenge ' whether [a warning] would have saved the plaintiff from injury without knowing the specifics of the proposed warning.” Id. at 24. The defense lawyer should persuade the court to require the plaintiff to detail the warning he contends should have been given. Regardless, the defense should pin down the plaintiff and his expert on specifics of their warning claim.

Police Admissibility of Plaintiff's Proof. In some courts, the plaintiff's testimony that he or she would have read and heeded a warning is too speculative to be admitted. See Magoffe, 375 Fed Appx. 848. Expert testimony on causation issues, e.g., an untested warning would have prevented the accident, may be unreliable under Rule 702 or its equivalents. Defense counsel should move to exclude speculative and unreliable testimony.

Prove Product User's Awareness of Risk. Plaintiff's prior awareness of the risk will defeat causation. If the plaintiff knows the risk, a warning would not have changed his conduct. See Ramstad v. Lear Siegler Diversified Holdings Corp. , 836 F.Supp. 1511 (D. Minn. 1993) (failure-to-warn claim dismissed when plaintiff was aware of danger presented by grain auger intake).

Proving the product user's knowledge is an effective strategy in cases involving a sophisticated user who helps the plaintiff make decisions on product use. For example, the knowledge level of the plaintiff's treating physician who prescribes a medical device or pharmaceutical must be explored. If the physician is already aware of the harm that allegedly should have been addressed by a different warning, then the existing warning did not factor in the physician's choice of the device or drug, or in providing informed consent to the patient/plaintiff. Ackermann v. Wyeth Pharms ., 526 F.3d 203 (5th Cir. 2008) (physician aware of suicide risk and would have prescribed drug even if different warning provided).

Prove Product User Did Not Read the Warning. Lack of, or inadequacy of, a warning is not causal if the product user did not read the warnings accompanying the product. If the defendant can prove that the user did not read the product's warnings, the failure-to-warn claim should be dismissed. Motus v. Pfizer , 358 F.3d 659 (9th Cir. 2003) (inadequate warning claim dismissed when prescribing physician did not read warnings before prescribing drug).

This approach may not work if the plaintiff claims that he did not read the warning because it was not conspicuous enough, e.g. , was not of a proper color or size, or was buried in the manual. See Bowbeer, et al., Warning: Failure to Read This Article May Be Hazardous to Your Failure-to-Warn Defense, 27 Wm. Mitchell L. Rev. 439, 460 (2000) (“[F]ailure to read the warning because the warning was not noticed in the first instance can raise the issue of the warning's adequacy, a question of fact, which may preclude judgment as a matter of law.”).

Similarly, if the product user admits he habitually does not read warnings, then failure-to-warn cannot have caused the accident. Even if an adequate warning appeared on the product, the plaintiff cannot prove he would have read and heeded it.

Prove Product User Does Not Heed Warnings. Even if the plaintiff shows that the user read the product's warnings, evidence that the user frequently disregards warnings may defeat causation. Evidence that the plaintiff smokes, drinks while pregnant, or does not use seat belts, despite relevant warnings, will help prove that he or she would not have heeded the proffered safety messages. The court may require the defendant's evidence of disregard of warnings to be related to use of the product involved in the accident, and to reach the level of habit, rather than anecdotal character evidence, to be admissible on causation. See, e.g., Sharpe v. Bestop, Inc. , 730 A.2d 285, 286 (N.J. 1999) (“habitual disregard” of seat belt warning admissible, hile “occasional disregard of warnings not to drink and drive” not admissible).

Offer Expert Testimony That Proposed Warning Would Not Have Affected Conduct. Defense experts may offer opinions that the plaintiff's proposed warning's effectiveness is untested or questionable. Communications or industrial psychology experts may also explain that the product user was habituated to using the product and a warning would not have affected his conduct. See Martin, et al., 'If Only I Would Have Been Told ” A Failure-to-Warn Discussion: Causation, the Uncertainty Principle, and the Benign Experience Principle,” 40 Product Safety & Liability Reporter 879 (2012).

Explore Other Evidence to Defeat Causation. Each case presents unique facts, which should be explored for causation defenses. For example, lack of warning may not be the cause of the accident if the plaintiff learned to use the product by earlier, frequent use of a similar product made by another manufacturer. Or a warning may be irrelevant when the plaintiff must make a split-second decision about product use. Or the plaintiff may not be able to prove that the manufacturer could have delivered an effective warning to the user. See, e.g., Huitt v. Southern California Gas Co. , 188 Cal. App.4th 1586 (Cal. App. 2010) (plaintiff failed to prove that warning by natural gas supply company that odorant could be adsorbed by new steel pipes would have reached plaintiff).

Rebut the Read and Heed Presumption. The same evidence offered to defeat causation may burst the heeding presumption, requiring the plaintiff to offer evidence that an adequate warning would have been read and heeded to get his claim to the jury. Evidence that the user was aware of the harm and confronted it anyway, or did not read the product labels, or does not customarily read warnings may defeat the presumption. See Bowbeer, Warning: Failure to Read This Article ' , 27 Wm. Mitchell L. Rev. at 462-63.

Move for Summary Judgment or to Dismiss When Undisputed Facts Defeat Causation . If the defense develops undisputed evidence defeating causation, e.g., the plaintiff was aware of the risk or did not read the challenged warning, it should seek dismissal of the failure-to-warn claims at summary judgment or at trial before submission to the jury. If the record is fully developed, the defendant may win summary judgment when there is no evidence to support causation. Koken v. Black & Veatch Constr., Inc. , 426 F.3d 39, 49 (1st Cir. 2005) (summary judgment appropriate where plaintiff failed to offer proof that “foreman would have ordered a course of action different from that which occurred” if he had received a warning).

Move to Dismiss When Plaintiff Fails to Prove Causation. In a state that has not adopted the heeding presumption, or if the presumption is rebutted, the plaintiff's failure to offer evidence at trial that the product user would have read an adequate warning and changed his conduct to avoid the risk should result in dismissal of the failure-to-warn claim. At the conclusion of the plaintiff's case, defense counsel should make a Rule 50 motion for judgment as a matter of law. See, e.g., Huitt, 188 Cal. App.4th at 1589 (trial court should have dismissed failure-to-warn claim when “there was no evidence that, had the [defendant] issued a warning, [plaintiffs] would have been aware of it”).

Conclusion

While duty and adequacy issues may predominate in failure-to-warn litigation, the causation issue is equally important and may be more challenging. Even if they pursue the claim in a state with a heeding presumption, plaintiffs' lawyers must prepare a strategy to prove that absence of an adequate warning caused plaintiff's loss. Defense counsel must plan to defeat causation at all stages of discovery and trial. The failure-to-warn claim is more likely to be resolved justly with proper focus by the parties and the court.

George W. Soule , a member of this newsletter's Board of Editors, is Partner at Soule & Stull LLC in Minneapolis. Kevin P. Curry is Counsel at the firm.