Wonder how many other policies are determined by studies of questionable scientific merit. ? Cholestrol, waste management, public education, tax spending or just name it. If you don't like something, just grab a study that says what you want, grab some signatures and take it the the appropriate politician, bureacrat or other person of authority and vola! If your cause has the lubricatian of liberal sentiment success is insured.
It's called Junk Science. And it's horrible. When a special interest group gets ahold of unreliable information and pushes it to the forefront as the gospel, they try to create a snow ball going down hill.