California’s Proposition 19, which would legalize marijuana, might slash the price of pot 80%, from $300–450 per ounce to $38, according to Rand:
The report noted that it was impossible to predict tax revenues from the initiative, which leaves that decision to cities and counties, but concluded that revenues from a statewide $50-per-ounce tax could range from $650 million to $1.49 billion.
To calculate the price drop, researchers looked at the cost of growing marijuana in a 1,500-square-foot house. The researchers concluded that the wages paid to employees who tend the crop would slip from as much as $25 per hour to no more than $10, just a little above what nursery laborers earn.
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Researchers also looked at estimates of the cost of enforcing marijuana laws in California, which range from $200 million to $1.9 billion, and put it at “probably less than $300 million.” They also concluded that it is not possible to determine whether increased use would lead to more drugged driving accidents and to more use of harder drugs, such as cocaine, finding that the research is inconclusive.