You may become aware of a headline in the papers today with variations of "Streets where more people died AFTER 20mph limit came in ...but councillors say it's too expensive to scrap it".
These reports are bogus and just like the famous Freddie Starr headline are untrue.
In April 2017 the new council administration in Bath and North East Somerset (that had opposed 20mph limits when in opposition) produced an analysis of results of speeds and casualties after implementing 20mph limits. The data in the report showed that :-
- Crashes in the 20mph limits had reduced by 28% in Bath.
- Casualties in the 20mph limits had reduced by 23% in Bath.
- The number roads with average speeds at or above 24mph had reduced by 43% when 20mph was implemented.
- The number of roads with average speeds at or above 26mph had reduced by 78% when 20mph was implemented.
Now you may feel that these would have been worth mentioning as a finding in the report but they were excluded. Instead the report found that by looking at areas in detail they could compare the number of areas where casualties and crashes had increased or decreased without weighting or taking any note of the significance of a number. And from this they concluded that more areas had increased casualties than reduced them. This is completely bogus statistically and we wrote a detailed critique of the report which may be viewed here
Subsequently in July the BANES Transport and Environment Policy Development and Scrutiny Panel reviewed their report and whilst noting its contents decided to take no action as a result. Read the minutes here.
Recently a local paper (Bath Chronicle) wrote an article around a story of a local resident complaining about 20mph limits and the deputy leader saying that the council could not afford to change the 20mph limits back to 30mph. The article referenced some parts of the April report from the council which had been found wanting by our critique and been ignored by the Traffic Committee. These included referencing that there were more areas of Bath where KSIs had increased than decreased. Note that the numbers in the report are quite low and we are often talking about a comparison between +0.2 or -0.2. There was no detail in the report for "fatalities".
This Bath Chronicle article was then taken up by the nationals with increasing alarm. The dubious comparison of very small quantities of killed or seriously injured was morphed into "Streets where more people died AFTER 20mph limit came in ...but councillors say it's too expensive to scrap it"
It is all lazy "cut and paste" journalism without any reference to the actual report or evidence. As we said in our critique back in May :-
"20’s Plenty for Us refute the findings and conclusions in the report and advise members that the report is so compromised that it would not be reasonable for them to make any decisions based on the report. This critique looks at the report in detail.
In particular it finds the report biased, lacking in statistical rigour and not meeting several local authority duties on competency and equality."
So lets be clear.
"20mph limits in Bath have successfully reduced speeds and reduced casualties. They are a welcome addition to making Bath an even better place to be for residents and visitors. The recent press articles are as useful to the 20mph debate as the Freddie Starr hamster story is to animal welfare."
ps The Freddie Starr story was found to be untrue during the Levenson Enquiry.
See an independent analysis made of the Bath report by the evolutionary biologist Lewis Spurgin on the website Medium
Hear Rod King's interview with BBC Radio Bristol's Laura Rawlings at https://t.co/svALEMit0S from 11:55
In the latest development on 20th Dec Bath Chronicle writes Bath Chronicle article on how the report failed to be endorsed by their own scrutiny panel back in July. And on 21st Dec the Bristol Post prints an article on "Why Bath council was wrong about 20mph zones increasing deaths and injuries on roads"