Ask HN: What are your favorite examples of science driving good policy?

Technocracy generally doesn't work, nor does science as religion. Science should inform not dictate. And in areas relevant to policy it's never black and white anyway, so just becomes a proxy for some underlying political debate. I don't know that there's such think as a good policy based on "science" saying something.

Maybe some areas of aviation, like definitions of twilight? Surveying laws? It would be banal stuff like that

Are phrenology and lysenkoism examples of science? Both had theories and beliefs but both failed to follow up with the hypothesize, test and refine parts of the science loop.