On behalf of Sandy Steel: 

 

For what it's worth, the phrase 'material contribution' does seem to come
from C19 Scottish (nuisance) cases.

Whether anyone, and if so who, is to blame for the present state of the
law, is, of course, a wholly separate matter. I agree with Martin that the
case against the Scots is pretty untenable.

Finally though, it's worth remembering that, even if the law manages to
dethrone the but-for test, and install NESS, the claimant ought, as a
matter of general legal principle, to lose if its damage would have
occurred, on the balance of probability, in any event. The problem is that
the law seems to be courting NESS whilst at the same time applying an
unarticulated exceptional proof rule in the assessment of the claimant's
damage (i.e. liability in solidum without proof on the BoP). If we are to
have NESS, these two should be disentangled. Whether we should have NESS is
a separate question; I am still unsure whether bringing quite refined, and
technical-philosophical notions of "causal sufficiency" into legal
discourse is a good idea.

Sandy Steel