I recall claims that interpersonal violence went down in western Europe prior to the restriction of firearms there, and similarly that many labor laws trailed general practice rather than led them. That is, child labor was already on its way out when laws against it came in; workweeks were already greatly reduced in many areas, and legislation served to scoop up those areas where there was no competition for labor and employers could abuse their workers, to bring them in line with the general beliefs of the society.
It sounds plausible, certainly, but is it true? My quick search on labor laws seem to come from sources biased one way or another. It would likely apply in many areas: zoning, treatment of women, product safety, drinking, slavery. It would make sense that societies would not put forth a lot of energy in moralities that were not generally shared.
Sense, yes. But humans do not always act sensibly, especially when it comes to telling everyone else what to do. What do you think? Do we know anything of hard evidence for or against this theory? Does law tend to be enacted only when there is considerable agreement already in the larger culture? Is this no longer the case in the last few years or few decades, when decisions are made at high levels about fairness and virtue, which are then imposed on the rest of us? Or was it worse 2-7 centuries ago?