"Asked whether they thought it should be legal to sell marijuana if it were legal to use it, about three in five (62%) said 'yes.' However, about 80% of those answering 'yes' (51% of all respondents) would permit sale only to adults. A small minority (11%) favored the sale to anyone, regardless of age, while 28% said that sale should not be legal even if use were made legal, and 10% said they 'don’t know.'"

Source

Johnston, L. D., O’Malley, P. M., Bachman, J. G., & Schulenberg, J. E., Monitoring the Future national survey results on drug use, 1975–2011: Volume I, Secondary school students," Institute for Social Research (Ann Arbor, Michigan: The University of Michigan, 2012), p. 379.
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