L.A. County officials wanted to solve its homelessness problem by way of a new “millionaire’s tax.” But, when it learned it did not have the authority, it went after the sick – that is, medical marijuana patients.

Voters in Los Angeles County will vote this fall whether marijuana businesses should be taxed to help pay for housing and health services for homeless people.

The Board of Supervisors approved Tuesday the ballot measure. L.A’s homeless population has been increasing. The cannabis tax is part of a larger scale effort by city and county representatives to raise more funds to alleviate such problems.

The board voted 3-2 to approve the measure, which calls for a 10% levy on gross receipts of cannabis businesses. Both the medical marijuana and the recreational marijuana industry would be affected. County analysts believe the measure could bring in upwards of $130 million a year – especially if California voters legalize recreational. Officials believe the medical marijuana industry would account for $13 million per year in pot taxes. If  legalized, taxes would not be collected on recreational marijuana until 2018.

The Los Angeles Housing Services Authority believes there are approximately 47,000 homeless people throughout the county. L.A. County Sheriff Jim McDonnell recently wrote that the homeless situation in the county is “dire.” He wants officials to come up with solutions beyond the pot tax.

Los Angeles does not know how it will collect taxes on an industry operating largely in cash. Treasurer-Tax Collector Joseph Kelly noted the office might hire armored cars to collect the cash.