I'm pretty sure there is no specific reference to marijuana in the Bible, but that can be said about many things. We do know many basic things that can always be used to define the rightness or wrongness of certain actions. For this particular situation, I would consider two things. The first is that God does not want you to disobey the law, unless following the law would cause you to dishonor God. The second would be that God certainly wants you to keep your body healthy, and anyone, with remotely any knowledge on the subject, can point out several health risks that are caused by use of marijuana. There are probably 100 other basic bibical principles that could be used to address the situation, but no need to list all of them. See if you can find any Bibical principles that would encourage use of Marijuana...I would be surprised if you could.