Expert Witness Journal Issue 67 June/July 2026 - Flipbook - Page 88
The Defendant’s position was accepted by the Court.
The Learned Judge agreed that there is insu昀케cient
scienti昀椀c evidence to support the notion that noise
causes latent damage to hearing. The Learned Judge
went on to conclude that:
individual on a percentile below the 50th would thus
be overcompensated. But on the other, the percentile
might be adjusted upwards (i.e. in favour of the
Claimant) by the operation of paragraphs 2 and 3,
if an individual shows better than average hearing
at only one threshold and, if that threshold is in the
better hearing ear, in only one ear. That is plainly
unjusti昀椀ed.
554. I also agree with Mr Platt that even if the
acceleration theory was su昀케ciently plausible as to be
viewed as “probable”, which in my view it certainly
cannot at present, it cannot properly be applied to
the circumstances of any given case or individual.
Furthermore, Mr Platt is right that even if the theory
is demonstrable and a mechanism can be conceived
whereby it could be identi昀椀ed in a given individual,
there is no way in which accelerated loss can be
accurately quanti昀椀ed in such a fashion as to make a
secure foundation for any award of damages.
476. In my judgment, the proper course is that the
choice of the percentile in the relevant dataset should
be dictated by the clinical judgment of the medicolegal
ENT surgeon based on the hearing pro昀椀le of the
individual as ascertained from all the available
audiometry.
Secondly, as to appropriate frequencies over which
to calculate disability, the Claimants had sought
to argue that the Court should depart from the
conventional use of an average over 1, 2 and 3 kHz
to an average over 1, 2 and 4 kHz. Having considered
the literature at length, the Court concluded that:
555. In those circumstances, it is my conclusion that
the theory that hearing loss may continue to develop
after exposure is plausible, intellectually coherent but
a very long way from being proven in human beings.
The orthodox view that hearing loss does not progress
after exposure ceases has not, at least at yet, been
displaced.
498. …On the evidence I have seen, it is clear that the
traditional 1, 2, 3 kHz average remains a reliable,
if conservative, measure of hearing disability,
supported by longstanding practice and by parts of
the literature that continue to recognise its adequacy.
At the same time, the scienti昀椀c material relied upon
by the Claimants, notably Smoorenburg and Moore,
suggest that frequencies above 3 kHz, and 4 kHz in
particular, play an important role in the perception
of speech in noisy environments, sound localisation,
and recognition of environmental sounds.
Cochlear Synaptopathy
As set out by the judge at [557], the expression
“cochlear synaptopathy” refers to a loss in the connections
(‘synapses’) between inner hair cells in the cochlea, the part
of the ear which detect sounds, and the auditory nerve
昀椀bres, which carry the signals from the inner hair cells to
the brain. The relevance of this issue to this litigation is that
such synaptopathy might lead to individuals experiencing
hearing di昀케culties (sometimes referred to as ‘hidden’
hearing loss), even if they have audiometric thresholds
within the normal range.
499. I conclude that, while the conventional 1, 2, 3
kHz average should continue to serve as a baseline
descriptor, it is entirely legitimate to consider 1, 2 and
4 kHz, particularly where speech-in-noise di昀케culty
is a prominent feature of a Claimant’s disability. It
should be for the ENT expert to identify which metric
best represents the Claimant’s disability. The modest
numerical di昀昀erences do not undermine the utility
of either approach; rather, they indicate that both
metrics should potentially be available to the Court,
with the weight to be attached to each depending on
the factual and audiometric circumstances of the
individual Claimant.
Latency
The Claimants had sought to argue that exposure to
impulse noise accelerates the future progression of
age-associated hearing loss. The Defendant stood by
the ‘orthodox’ view that noise damages hearing at
the point of exposure.
This was an extremely signi昀椀cant issue in the
litigation, particularly when taken together with the
reliability of military audiometry, and is likely to be
determinative of a signi昀椀cant number of claims in
the cohort.
EXPERT WITNESS JOURNAL
86
JUNE 2026
