We return now to helmets since they are, beyond a doubt, the most often touted measure to increase motorcycle safety. In the next two entries, we will examine one state’s data over the same ten-year period we looked at in terms of crashing. What we will find illustrates many of the problems with motorcycle safety:

Louisiana is a unique case when it comes to motorcycle safety: Like almost all other states, a universal helmet law was passed in the 1960s (1968, to be exact) and then modified it in 1976 to only apply to those under 18. Then legislators passed a universal helmet law again in 1982. Seventeen years later, the law was modified once again to require only those under 18 or those without coverage of at least $10,000 in medical insurance to wear a helmet and was in effect in August of 1999. Five years later, in 2004, the universal helmet law was reinstated.

During the same time frame that we examined crashes in terms of three kinds of crashes (fatalities, injuries and property-only crashes), then, Louisiana didn’t have a universal helmet law and then did have one. It is, then, a good state to see the effects of helmet and non-helmet use and the effect of a helmet law in terms of fatalities and injuries. In this entry we look only at fatalities.

Louisiana in comparison to national picture

As in the rest of the USA, motorcycle fatalities increased from 40 in 1998 to 87 in 2006 or 117.5 percent. In 2008 fatalities were 77 or 92.5 percent and then to 92 in 2009. Overall, then Louisiana’s fatality toll rose 130 percent in eleven years. This is over the national percentage over the same time span.

As in the rest of the USA, motorcycle registrations were increasing in Louisiana during these years—though there are no publicly reliable statistics to document the increase—not even for NHTSA.[i] While the researchers who prepared the report on the effect of the helmet law repeal dismissed the importance of increasing registrations on crash rates, others would strongly disagree. As we’ve seen in other states we’ve examined, registrations did not increase unilaterally in every state nor from year to year. The missing data, then, leaves a huge gap—if motorcycle safety is a puzzle, then this is information we need to solve it.

Observed helmet use over the ten years

In the years when the universal helmet law was in effect, between 87-100 percent of riders wore them. In the years without mandated helmet use, usage dropped immediately to 52 percent then rose to about 60 percent, dropped to 48 percent rose again to about 60 percent and stayed there until the universal helmet law was reinstated when observed helmet use appears to be 98-99%.

Unsurprisingly, when helmet use dropped unhelmeted fatalities went up[ii] and helmeted fatalities went down. And, unsurprisingly, when the mandate was reinstated, helmeted fatalities went up.[iii]

Studies were done, papers and reports were written to document the effect of the helmet law repeal—and then the reinstatement. Including NHTSA who released a report, “Evaluation of the Reinstatement of the Motorcycle Helmet Law in Louisiana”.

And the stats were astonishing—unhelmeted fatalities increased by 40% the first year and 42% the second year after the repeal and dropped 64% the year after the universal helmet law was repealed. It seems to prove the case—and is religiously held by helmet proponents: helmets save lives.

And, as helmet-proponents would expect, helmeted fatalities were under-represented compared to observed helmet-use:

And unhelmeted injuries were over-represented to non-use:

The helmet story seems to be justified.

However, if we look without preconceptions more closely at the actual numbers, that’s not the full story—and by not telling the full story, motorcycle safety researchers have not served riders well. The data in the following chart Data taken from the Louisiana State University Traffic Safety Research Group traffic safety data reports.

UnHelmet Fatalities Year-to-Year ChangeUnH Estimated Non-Helmet Use Total F Fatality Increase from prior year Observed Helmet Use Year-to-Year Change HEL Helmet Fatalities 1999 15 3% 40 14.2% 97% 25 2000 21 40% 48% 50 25% 52% 16% 29 2001 36 42% 41% 53 6% 59% -41% 17 2002 41 14% 58% 58 9.4% 42% 0% 17 2003 55 34% 40% 77 32.7% 60% 29% 22 2004 36 -34% 40% 68 -11.6% 60% 45% 32 2005 13 -64% 2% 70 -2.9% 98% 78% 57 2006 8 -38% 2% 87 24.2% 98% 38% 79 2007 14 43% 73 -16% -25% 59 2008 19 36% 77 5.4% -1.7% 58 2008 15 -21% 91 18.1% 31% 76 Totals 258 653 395

The NHTSA report doesn’t note that once the law was reinstated,

helmeted fatalities went up 45% then 78% then 38%. Iow, equally scary percentages are found on both sides of the Louisiana Experiment.

In fact, in 2004—the year of reinstatement—unhelmeted fatalities dropped 23—but helmeted fatalities rose 25. It’s almost as if it was simply a trade-off: unhelmeted deaths became helmeted deaths. This is the first indication that even though helmets save lives, their absence doesn’t drive the increase in motorcycle deaths.

While it is true that unhelmeted fatalities increased every year, however helmeted fatalities also increased 8 out of the 10 years—and that included two years when helmet use was depressed. This is the second indication that helmet use is disconnected from the rise or fall of fatalities in essential ways.

Ultimately this is the scariest thing of all: During these years, Louisiana’s motorcyclist death toll soared and helmeted fatalities tripled while unhelmeted fatalities in 2008 returned to exactly what they were in 1999.

The large point is this: the issue isn’t helmet effectiveness. Focusing merely on helmet use or encouraging riders to wear them simply doesn’t address why those fatal crashes are occurring more and more often. In this way, the increases on the helmeted side of the equation are more troubling since the additional protection helmets offer were insufficient in preventing deadly injuries. We’ll return to this point in the next entry.

In reality, small numbers

But the focus on helmet use disguises something that is also essential to really understanding what’s happening with riders: small numbers make for big—but misleading—percentages on both sides of the equation. And in Louisiana, the numbers are sometimes very small:

2000: Helmet use was 52%. Fatalities increased by 10 riders.

Unhelmeted fatalities up by 6.

Helmeted fatalities up by 4.

2001:Helmet use: 59%. Death toll increased by 3.

Unhelmeted fatalities went up by 15.

Helmeted fatalities down by 12.

2002: Helmet use: 42% fatalities. Fatalities up by 5.

Increase was solely accounted for by unhelmeted deaths.

2003: Helmet use 60%. Fatalities up by 19.

Unhelmeted fatalities up by 14.

Helmeted fatalities up by 5.

2004: Helmet law use 60%. Fatalities down by 9.

Unhelmeted fatalities down by 19.

Helmeted fatalities up by 10.

2005: Helmet use was 98%.[iv] Death toll increased by 2.

Unhelmeted fatalities down by 23.

Helmeted fatalities up by 25.

2006: Helmet use 98%. Fatalities increased by 17.

Unhelmeted fatalities down by 5

Helmeted fatalities up by 22.

2007: Estimated helmet use 98%. Fatalities decreased by 14

Unhelmeted fatalities up by 6.

Helmeted fatalities down by 20.

2008: Estimated helmet use 98%. Fatalities increased by 4.

Unhelmeted fatalities down by 5.

Helmeted fatalities up by 18.

Small numbers yield large percentages—but skew the interpretation

There’s several things to observe: If fatalities can legitimately be expected as a function of the numbers, some kind of increase could be—and maybe should be—expected because motorcycle registrations were increasing. But even as the pool of motorcyclists was growing fatalities increased by 5 or less in four of the ten years.

And 5 or less are surely small numbers—and yet they can loom large and appear to be more important than they perhaps are. For example, a decrease of unhelmeted 5 deaths in 2005—the year after the helmet law reinstatement—resulted in a decrease of 38% and an increase in 5 helmeted deaths results in a 29% increase. Using percentages to make a point without including the numbers can lead to inaccurate analysis and, in this case, exaggerate the supposed effect of the reinstatement when the reality is that people who might have died without helmets died with them on.

A pattern of wild fluctuations

Louisiana’s pattern is one of wild fluctuations where fatalities creep up or down by 5 or less or soar by 22 one year and plunge the next by 20 then rise to 18. This pattern of dramatic year-to-year shifts is not seen in states with large numbers of fatalities where they produce smaller percentages of increase.

Such wild swings raise the possibility that crashes have much more to do with random factors or at least factors that are not considered and therefore not accounted for than any crash causation study to date has considered.

While Louisiana’s motorcycle registrations are shrouded in mystery for some inexplicable reason, the state does provide data on injuries as well as fatalities—and that’s where we follow the helmet story next.

[i] Observed helmet use statistics interpreted from Evaluation of the Reinstatement of the Motorcycle Helmet Law in Louisiana, NHTSA, Number 346 May 2008.

[ii] The helmet law was repealed in August. The death toll went up by 5 but we don’t know if they were helmeted or not.

[iii] Evaluation of the Reinstatement of the Motorcycle Helmet Law in Louisiana.

[iv] Ibid. According to NHTSA and quoted in other studies.

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