After installing blue lights on Buchanan Street in Glasgow, Scotland, the crime rate dropped. At a railway station in Tokyo, the problem of suicide was serious. After installing the blue light, the death of the track jump completely stopped. At the Gatwick Airport train station outside London, for the same reason, a large-scale trial is being installed to install the blue light.
These obvious successes raise some compelling questions. For example, do these lights directly lead to a reduction in crime and suicide? If so, why?
Theories abound: unexpected colors are unpredictable and change their expected behavior; Blu-ray has a calming effect; Blu-ray is reminiscent of emergency services and first-aiders.
The British traffic police were very interested in this and investigated the phenomenon. Suicide and crime are just one of their concerns. The British police and local governments have been using blue lights in public places for years to reduce intravenous drug use. They want to understand the effects of Blu-ray on this and other applications.