Having declared Ford v. Dixon to be one of the best (and by that we meant most thoughtful, well-reasoned and game-changing) opinions in a long time the Maryland Supreme Court's follow-up in Georgia-Pacific v. Farrar had us seriously perplexed as we read its take on substantial factor causation. Eventually, however, we realized that Georgia-Pacific had played the Bostic gambit and now it all makes sense.

The first third of the opinion dispenses with the claim that product manufacturers have no duty to family members exposed to a toxin brought home on the clothes of a bystander. That argument rarely goes anywhere as most courts tend to Justice Andrews' view expressed in Palsgraf when the act complained of is the dispersion of an amorphous, flowing hazard; as in the case of asbestos exposure. Thus, when a court "because of convenience, of public policy, of a rough sense of justice ... arbitrarily declines to trace a series of events beyond a certain point", it then must ask: does there exist a yardstick that might fairly reasonably, generally reliably and somewhat predictably allow it to draw such a line?  We've been saying for years that in the case of well-studied toxins there is - it's the approximate risk imparted by the particular dose.

When the risk imparted is so slight that imposing liability for it would be counterproductive or unfair (because, for example, life is rife with inevitable risks and the one in question is by comparison de minimis) a court ought to conclude that no duty is owed. When the risk is more than merely de minimis the jury, or court sitting as fact finder, expresses the community's view of whether the risk imparted was substantial - which is to say that it was, or was not, acceptable. And that's what Ford v. Dixon held. Instead, in Farrar G-P went up on yesteryear's causal theories: 1) regularity, frequency and proximity; 2) "any exposure above background" is not enough; and 3) any cause for which liability may attach must also be a sufficient cause.

In Farrar, a take-home case, the regularity, frequency and proximity test was easily met. Plaintiff's grandfather worked construction in the Forrestal Building for months and routinely was exposed to the defendant's product; the dust from which settled on his clothes which were then regularly shaken out and washed by plaintiff. The resultant exposures were estimated to be very high (though plaintiff's expert's claim that any time you see any sort of dust Merewhether's 5mppcf level for asbestos has been exceeded, goes nowhere here in his home state). An easy win for plaintiff.

G-P next complained that plaintiff had not established substantial factor causation. Unfortunately, "Georgia-Pacific never argued that the jury was led to believe 'that any exposure to any purportedly "low dose" of asbestos above background levels is a substantial factor in causing mesothelioma'. This is a new argument on appeal and thus has not been preserved", wrote the Maryland Supreme Court. Yet it decided to address the merits of G-P's argument anyway. Luckily for plaintiff, G-P decided to try the Bostic approach - which is to say it argued plaintiff must show that each exposure to asbestos "was sufficient to cause mesothelioma". Can you say "overreaching"?

As we've said repeatedly, the idea that a plaintiff must show that each defendant's contribution to her cumulative dose was a sufficient cause of her harm is manifestly unjust in any multidefendant toxic tort case  - see e.g.Borel v. Fiberboard. And frankly, the injustice worked by such a rule wouldn't be limited to toxic tort cases. Any case in which multiple acts were "but for" causes of a single harm would see all the defendants excused. Indeed, any case in which an act of the plaintiff herself was found to have been the proximate cause of her own harm would see every defendant walk since their conduct, however egregious, necessarily could not have been a sufficient cause of plaintiff's harm. Such a holding then would basically reconstitute the old contributory negligence bar. And nobody's going there; including the Maryland Supreme Court.

Ford v. Dixon recognized that we live in an age of acknowledged uncertainty; of risk. Thus when an expert said a risk was substantial but couldn't say how, or why, the Court ruled that "such testimony 'lacked any information that would "assist the trier of fact to understand the evidence or to determine a fact in issue'..." That fact issue being: whether or not the risk imposed was substantial. When G-P fought not on risk but on Lohrmann it failed to appreciate just how much causal thinking has changed in the last 25 years. Upon sensing at last the change that's afoot G-P tried the new approach, but was too late. The Maryland Supremes wrote "It would be fundamentally unfair to the litigants to decide this case on an issue not raised at the trial court nor, for that matter, briefed to us." And so G-P lost.

Dose is the measure of risk, and risk is the measure of substantiality. Get it?