A more evidence based approach to the 20mph discussion http://www.rospa.com/rospaweb/docs/advice-services/road-safety/drivers/20-mph-zone-factsheet.pdf (Admittedly I've only skimmed it).
@aggi started
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A more evidence based approach to the 20mph discussion http://www.rospa.com/rospaweb/docs/advice-services/road-safety/drivers/20-mph-zone-factsheet.pdf (Admittedly I've only skimmed it).