Good questions.
2.
http://www.dmv.org/ca-california/automotive-law/dui.php#California-DUI-Defined3. California would probably tax the marijuana at least as much as tobacco.
4. It ought to have the same warnings as tobacco, be banned in public places, around children, and have an additional warning regarding intoxication.
5.
http://www.drugabuse.gov/publications/drugfacts/marijuanaThe last question is one avoided by most marijuana advocates and consumers.
Illegal drugs and the miss-use of prescription drugs are cancers in our society.