It hasn't been debunked , though pot heads and they're supporters keep claiming has been.  The reason I'm strongly against pot is what it does to kids. The more pot that's out there , the more they will get into it. The developing mind of young people can be altered for life by it's use.  It's about protecting our kids. Let older adults do whatever they want to wreck they're lives. If they're head was screwed on right they wouldn't feel the need to get high all the time.