The question is, how do you prove it?
In the recent case of Tayside Contracts v D Geddes (Contractors) Limited an interesting approach was taken to establishing a claim against the supplier of certain building products. Although the case itself concerns issues of fault with aggregate used for the construction of roads, and is therefore by its very topic a little dry, it makes for interesting reading if only to note a novel approach taken by the pursuer to the thorny issue of proving a claim.
Going back to basics there are three critical stages which a party has to reach in order to establish a claim. First, there needs to be a wrong. In this case, the aggregate supplied didn't seem to work properly and was therefore apparently unsuitable for road surfacing. That wrong needs to have been caused by something and the event which caused the wrong must have resulted in a loss.
In this case, the pursuer sought to run three possible arguments to establish liability, or the cause of the failure in the road surfacing. These three approaches were all separate and distinct, one of them had to be the cause?
Not a bare knuckle fist fight but rather a phenomenon where chips of the sort used in aggregate, absorb moisture, degraded while stockpiled and turned (at least partly) to dust. Sadly, there was no evidence led, or indeed available, to the effect that dusting up had actually occurred in this case.
No joy with argument number one. On to the next…
Reminder - this is a case about road surfacing, nothing more exotic to consider. The second argument was that the make up of the aggregate meant that it was liable to break the bond between the stone and the bitumen - effectively a failure to stick together properly. The judge wasn't convinced that the evidence here worked either. Time to try again…
The third way, elimination of all other possible causes.
Although the aggregate was compliant with industry standards and even if the specific causes of failure could be rejected (ie arguments 1 and 2), the court was asked to find that an unknown feature was the source of the failures. If it's not A or B, it must be C (although we don't know why). As Lord Docherty put it "The Submission was a bold one."
This third way was rejected for want of evidence. No evidence was produced to support a proposition that an unknown characteristic of the aggregate was responsible for the failures. Where all of the relevant facts are unknown, a process of elimination is inappropriate. Lord Docherty took the view that on the basis of the evidence the cause or causes of the failure of the road surfaces was unknown and unproven.
The moral of the story is that although where there's blame there may well be a claim, that claim has to have a foundation in facts which are capable of proof. That is to say, a failure to prepare, is a preparation for failure.