Michigan Penalties It's illegal to possess any amount. See the link for fines/jail time. The one exception I can think of is Ann Arbor. First time offense, if charged under local laws, is $20 and no jail time.
Smoked marijuana has not withstood the rigors of science – it is not medicine and it is not safe. There is no consensus of medical evidence that smoking marijuana helps patients. Congress enacted laws against marijuana in 1970 based in part on its conclusion that marijuana has no scientifically proven medical value. The American Cancer Society "does not advocate inhaling smoke, nor the legalization of marijuana," although the organization does support carefully controlled clinical studies for alternative delivery methods, specifically a THC skin patch.
Marijuana was first tried for Illegalization in the early 1900's. Later like you said in 1970 it was finally deemed Illegal because users of the plant had "Erratic Behavior" and other cases where people would beat other people down mercilessly. What they never released until dirt got out that those people were on many other drugs too Including Alcohol. The guy that finally got Marijuana Illegalized despised Marijuana more than anything. The guy would rather see Meth or Coke on the streets than Marijuana. Now it is used for AIDS treatment, Glaucoma, cancer, and pain relief. Every Medical Purpose that is used medically has been proven and tested for a 100% fact that it IS the best treatment available for those conditions. So yea. Next time you decide you are going to Troll a Marijuana forum. Get your shit together first dumbass.