On some days, it’s hard to get back into the routine.

We’d rather keep mining the depths of Colacicco to see what nuggets we can unearth there.

But we owe it to you to provide a short post about the California Supreme Court’s decision in Johnson v. American Standard, Inc., 179 P.3d 905, No. S139184, slip op. (Cal. Apr. 3, 2008) (here’s a link). When duty calls, there’s an outside chance that one of your humble scribes will rise to the occasion.

Here’s the deal: Product manufacturers must warn about certain dangers associated with using their products. But manufacturers don’t have to warn about obvious dangers — because people already know about them. Warning people about dangers they’re already aware of won’t change anyone’s conduct or avoid any accidents.

Suppose a manufacturer sells a product to particularly knowledgeable — sophisticated — users. An average person might not be aware of the risk associated with the product, but the people who actually buy the product are well aware of the risk. Must a manufacturer warn about non-obvious dangers of which the sophisticated users are aware?

(Astute readers will recognize that “sophisticated users” are, in many respects, a lot like physicians — who are sophisticated users of prescription medical products. Although the analogy may be imperfect in certain ways, we read sophisticated user cases in part with an eye toward how their analysis might apply in the drug and device context. More on that in a minute.)

In any event, William Johnson was a certified heating, ventilation, and air conditioning technician. He took a year-long course on HVAC systems and earned “universal” certification from the Environmental Protection Agency by passing a five-part exam. “Universally” certified technicians are trained in tasks that include welding air conditioning units.

Large air conditioning systems often use R-22, a hydrochlorofluorocarbon refrigerant, which can decompose into hazardous phosgene gas when exposed to high heat. Here’s what made this a relatively easy case: Beginning in 1997, every time Johnson bought R-22, he “received, and sometimes read, an MSDS” (material safety data sheet) that explained the risks associated with R-22. Johnson, slip op. at 2.

American Standard manufactured an evaporator that contained R-22 and was installed at a branch of the Bank of America. Johnson welded refrigerant lines on that HVAC system and later filed a product liability complaint pleading that he developed pulmonary fibrosis as a result of exposure to phosgene gas.

The trial court granted American Standard’s motion for summary judgment based on the sophisticated user defense. Johnson knew, or should have known, of the risks associated with R-22, so American Standard owed no duty to warn of those risks. The Court of Appeal affirmed, and the California Supreme Court in turn unanimously affirmed.

As drug and device lawyers, we particularly liked the Supreme Court’s language about the dangers of over-warning: “Not all warnings, however, promote user safety. Requiring manufacturers to warn their products’ users in all instances would place an onerous burden on them and would ‘invite mass consumer disregard and ultimate contempt for the warning process.'” Slip op. at 15 (citations omitted). The FDA has often used similar language to describe the decisions it makes when deciding what warnings should appear on prescription drugs and devices.

The Supreme Court went on to explain the contours of the sophisticated user defense in California.

First, the defense applies not only to users who were actually aware of a particular risk, but also to users who should have known about that risk. Id.

Second, the sophisticated user defense applies to both negligence and strict liability causes of action. Id. at 16.

Finally, the user’s sophistication is judged as of the date the sophisticated user is injured and knew or should have known of the risk. Id. at 19.

The court did not directly address one question: When the manufacturer sells not directly to a sophisticated user, but only to a sophisticated intermediary, and the product then injures a third party, does the defense nonetheless apply?

That omission doesn’t bother us.

The court cited with approval an earlier state court case in which the defendant sold a skeleton truck to a company that then installed a refrigeration unit on the chasis. When a truck driver was later injured in a fire, the court held that the manufacturer wasn’t liable, because the sophisticated intermediary, which installed the refrigeration unit, was aware that gasoline is volatile and sparks can ignite it. The manufacturer did not have to warn the sophisticated intermediary of those risks. Id. at 12.

The court also cited with approval a federal case that recognized the sophisticated user defense in the context of a sophisticated intermediary. When an asbestos manufacturer sold asbestos to a sophisticated intermediary — the Navy — the manufacturer could be absolved of liability for the Navy’s failure to warn its employees of the product’s danger. Id. at 13.

We’re confident that the California Supreme Court will hold that the sophisticated user defense applies when a sophisticated intermediary stands between the manufacturer and the allegedly injured party.

One last point merits thought:

We’ve often explained that the “learned intermediary doctrine” is just that — a doctrine, and not an affirmative defense. Plaintiffs bear the burden of proving causation as part of their case-in-chief. Plaintiffs must therefore prove that a different warning on a drug’s package insert would have changed the physician’s conduct and avoided an alleged injury. Because the learned intermediary doctrine is not an affirmative defense, defendants do not bear the burden of proof.

“Sophisticated users,” however, is described as a “defense,” not a doctrine. That may be appropriate because the defendant may bear the burden of proving that the user was sophisticated.

All physicians are presumed to be learned by virtue of those many years in medical school and residencies. Courts are not as naturally aware of the education of HVAC technicians, so defendants might be required to prove that HVAC technicians are sophisticated. In that sense, the sophisticated user defense requires a defendant to offer proof and is thus an affirmative defense.

Once the defendant makes that showing, the sophisticated user defense arguably becomes more potent than the learned intermediary doctrine. Sophisticated users are presumed to know the hazards associated with a product, and plaintiffs are forbidden to offer proof that a particular user was in fact ignorant of the risk. Thus, the sophisticated user defense eliminates liability for risks that the user should have known of, whether or not he actually knew of them.

That’s not the case in many states under the learned intermediary doctrine. In many states, so long as the physician was not in fact aware of a particular risk (and testifies that awareness would have changed the prescription), the manufacturer may still be on the hook.

Where’s the justice in that, we ask you?

Shouldn’t we drug and device lawyers be striving for that same standard in the learned intermediary context? If a physician should have known of a risk associated with a drug, the manufacturer should have no duty to warn. A manufacturer should not be blamed for a particular physician’s actual ignorance of a specific risk. After all, as the California Supreme Court wrote, “Legal duties must be based on objective general predictions of the anticipated user population’s knowledge, not case-by-case hindsight examinations of the particular plaintiff’s subjective state of mind.” Id. at 19 (citation omitted).

Perhaps defense lawyers should seek to broaden the learned intermediary doctrine to apply not only to risks that physicians did know about, but also to risks the physicians should have known about, independently from other sources. That interpretation would bring the learned intermediary doctrine in line with the sophisticated user defense.

(Frankly, we’re still turning that idea over in our minds. There’s a certain complexity to the physician’s decision-making — what does it mean, for example, for a physician to “heed” a warning? — that appears in the learned intermediary cases and may not apply directly in the sophisticated user context. But we plan to keep thinking about this until we figure out why it works, and how it helps us.)

Maybe that’s why we read sophisticated user cases.