In England, Katie Dagley, 19, died in an accident as bizarre as it was tragic. In something out of a proximate cause question on a torts exam, a traffic light-controlled bridge malfunctioned after a slug cause the lights to malfunction. That’s right, investigators believe that the slug left a trail across a circuit board that caused it to short out. That caused the lights to malfunction and Dagley proceeding against traffic on a one-land bridge in Tamworth, Staffordshire.
There are obviously superseding intervening acts and acts of God that cut off liability in torts. However, it strikes me as a bit odd to have an exposed circuit board that can short out with as little as a snail or slug passing over it. Such natural events would appear foreseeable. Of course, the utility or agency in charge could argue that this was a first such occasion or, as in Blyth v. Birmingham Water Works, had such a low probability that it was reasonable not to take precautions. However, it would seem under the Hand formula there is a basis to allege potential negligence. The commonly used formula is based on three elements: (1). Probability of harm (or likelihood of injury) = P; (2). Gravity of harm (or seriousness of injury) = L (loss or liability); and (3) Burden on defendant (or injury sacrificed) to take adequate precautions = B. It is unreasonable if B < P x L.
Here the burden (B) to avoid the accident would have been quite low to protect a circuit board. The loss (L) is quite high due to involvement of vehicles on a one-lane bridge. What is left is the probability (P). A slug-induced accident may be a first, but it may have occurred before and been treated as a simply burned out circuit board. Moreover, one would have had to look at all causes of shorting out a board due to the failure to protect it from insects, weather etc.
Source: Daily Mail