Relation of mobile phone availability to crashes in
Dr Paul Treffner
An analysis of Ministry of Transport
data on road fatalities and injuries from 1990 to
2018 shows that there is a strong correspondence between:
the widespread availability of mobile phones beginning around 2000 and
an increase in casualties,
(2) the introduction of NZ mobile phone laws
in November 2009 and a decrease in casualties, and
(3) the widespread
availability and adoption of new smartphone technology in 2013
and a sharp increase in casualties; this is in contrast to other countries.
Below is NZ MOT data as of mid-December 2018. Click to enlarge.
|Phone availability and road casualties in NZ
Unlike the above profiles show, the trend since the 1990s in many countries has been for a continual reduction in
However, in New Zealand this trend has stopped and has been increasing in recent years. Why is this?
Deaths per 1000,000 inhabitants (G7 countries in background; OECD data site):
The increase in road deaths and injuries since the minimum in 2013
may be related to the widespread availability and use while driving of
smartphones (especially texting) despite nominal, low penalty laws
The relation between mobile phone availability
and casualties is even more apparent in the dramatic increase in nonfatal injuries as compared to
deaths. As there are about 40 times more injuries than deaths, the disastrous effects on society of inattention due
to using mobile phones while driving may be vastly under-appreciated.
The Ministry of Transport data on road deaths is below (1990 - 2017). Why the upturn since 2013? That
is the question everyone is asking:
The MOT data on crashes due to fatigue and to diverted attention is shown below with 39 deaths in 2017:
The fatigue data shows no particular pattern other than an overall slight reduction from a maximum
of 76 in 1999. There are now more deaths due to distraction than to fatigue.
Note that "diverted attention", is far harder to determine from driver
self-reports or crash scene than an admission of fatigue by the driver.
Of course, falling asleep at the wheel is a dramatic form of inattention
The high point for deaths due to inattention (41) was just before the phone ban started being enforced
The dramatic drop was in 2011-2012 and is clearly probably due to greater enforcement and awareness
of the ban on phones.
The minimum (22) was in 2013 just before smartphones became widely
available. The deaths for last year (2017) were 39. I predict a new
maximum for 2018, perhaps 45 (if the increase continues).
It is also instructive to look at the effect of "speed". Has speed
contributed to the upturn since 2013? What about drunk/drugged driving?
Here is the data:
Speed or rather "speeding" as a primary causative does not seem
to have been responsible for the dramatic upturn in overall deaths
since 2013. However, drunk/drugged driving seems to be involved and is
easier to objectively determine (e.g., with a biological test).
Distracted driving is harder to legally prove and is clearly
underestimated by the policing authorities worldwide, but it is clear
from the huge amount of international studies both empirical (simulators
and on-road) and qualitative (surveys), and from plain logic, that this
is an epidemic in all countries now and urgently needs addressed in NZ.
One telling piece of evidence comes from young person
(15 - 24 yrs) deaths which have been increasing in recent years too.
Their pattern closely follows the pattern for deaths involving
inattention and, since 2005, is strongly correlated (.76) - ups
and downs in diverted attention casualties correspond with ups and
downs in young person casualties. Young drivers have consistently been
shown to text and drive at much higher rates than older drivers although
older drivers have high rates of phone use and texting too. As
expected, inattention deaths correlates strongly with all fatalities
(.75) since all fatalities data includes young persons data.
Alcohol/drugs casualties (in all age groups) is correlated with young
person casualties (.72) too, but less than is inattention (.76). It is
important to realise that for young persons, mobile phone use is very
high (e.g., typically at least 50% admit to texting). Therefore,
distracted driving is a significant factor in young person casualties
and needs to be addressed.
This is all compelling evidence for a significant relation between
distracted driving and road casualties in NZ and supports the concern
about drivers and distracted driving.
Actual data values for deaths:
When data on deaths from the groups involving: (1) inattention,
(2) alcohol/drugs, (3) young persons, and (4) all deaths is scaled
(using constant multipliers) so that they become superimposed,
visualisation of the correlations becomes apparent:
No more data is needed - we have plenty from MOT and research groups for the government to impose stiffer
penalties in order to discourage distracted driving and, especially, texting (texting should carry a special extra
penalty to that of talking on a phone).
Further consideration of the relation between mobile phone use and
casualties is warranted and a re-evaluation of mobile phone
disincentives (and penalties) is needed if NZ is to stop wasting time
and is to start to reverse this much-pondered and debated recent
increase in casualties and to see a reduction in road trauma to a level
similar to comparable countries.
Consider penalties for hand-held use of a mobile phone:
Penalties in UK: $400 and HALF of total points (6/12).
Penalties in NZ: $80 and only a fifth of total points (20/100).
Penalties in Australia are comparable to the UK (e.g., Queensland). Australia started banning phone use during 2000s and all states now
have mobile phone penalties as high as A$548 (ACT; for texting) and a
low of A$200 (NT; almost treble the NZ fine). New Zealand did not
introduce phone laws until November 2009.
Having conducted the world's first actual on-road studies of distracted driving I concur that inattentive driving is responsible for as much as 80% of all crashes (Treffner et al., 2002,
2004, 2008). Attention is a powerful but delicate thing (e.g., example of change blindness).
Where attention is directed can also alter motor control and
coordination in subtle and surprising ways (Amazeen et al., 1998;
Treffner & Turvey, 1995); an everyday case is driving. Further,
using a mobile phone, even hands-free, while driving always leads
to some degree of cognitive interference and in its worst form,
"inattentional blindness". This is a serious violation of the basic
expectations of care and respect for other road users. But in NZ the low
penalty of 20 points is even less than the misdemeanor of not displaying L-plates (25
points). The current historic and rather trivial penalty for phone use
does not acknowledge the serious damage inattentive driving is increasingly having
on society nor does it even attempt to address the problem by imposing
realistic penalties that would make careless drivers think
twice...unless they don't care about losing their license (or worse).
Should penalties be increased?
Three kinds of distraction: Visual, manual, and cognitive.
References on driving, attention, phones, and speech-hand coordination
P. J. (2018). Driver distraction - Is it that bad? Yes. Invited talk plus workshop at 43rd annual conference of NZ Institute of Driver
Treffner, P. J., Peter, M., & Kleidon, M. (2008). Gestures and
phases: The dynamics of speech-hand communication. Ecological Psychology, 20, 32-64.Try experiment.
Treffner, P. J., & Barrett, R. (2004). Hands-free mobile phone speech while driving degrades coordination and control.
Transportation Research, Part F: Traffic Psychology and Behaviour, 7, 229-246. Media coverage.
Treffner, P. J., Barrett, R., & Petersen, A. J. (2002). Stability and skill in driving. Human Movement Science, 21, 749-784.
Treffner, P. J., & Peter, M. (2002). Intentional and attentional dynamics of speech-hand coordination. Human Movement Science, 21, 641-697.
Amazeen, E., Amazeen, P., Treffner, P. J., & Turvey, M. T.
(1997). Attention and handedness in bimanual coordination dynamics. Journal of Experimental Psychology: Human Perception and Performance, 23, 1552-1560.
Treffner, P. J., & Turvey, M. T. (1995). Handedness and the asymmetric dynamics of bimanual rhythmic coordination.
Journal of Experimental Psychology: Human Perception and Performance, 21, 318-333.
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(c) Paul Treffner, 20/12/18