And run the risk that they’ll take their money and flee, you should at least write the law in such a way that the revenue can be used for other sources if it’s not used by a certain date. California is billions of dollars over budget and yet they can’t touch over $2 billion dollars that’s sitting in a bank account unused because it was collected to expand county mental health programs and can’t be used for anything else:

“As of March 31, 2008, approximately $3.2 billion has been collected and $2.9 billion has been allocated for county use. Of the $2.9 billion allocation, $1 billion has been approved for distribution but only $726 million has been distributed to the counties.” This means that $2.174 billion is just sitting in the bank unused.
Similarly, much of the funding that has been distributed to counties still is not being utilized and is instead being held in reserves. Total county Proposition 63 reserve funds statewide exceed $80 million. However, as we face a $27.8 billion budget deficit over the next 20 months, Proposition 63’s inflexibility prohibits counties from transferring reserves to fund other priorities.
The Department of Finance’s audit declares, “An overall documented plan for the development and implementation of the MHSA does not exist.” Furthermore, the audit cited ineffective communication between the Department of Mental Health, the Mental Health Oversight and Accountability Commission (an agency responsible for overseeing parts of the MHSA) and the counties. The audit states the Department of Mental Health’s application of Community Services and Supports (mental health services for children and adults) guidelines has been “strict and inflexible,” and counties have therefore developed plans ranging from 300 to 1000 pages that meet the guidelines but not the needs of their communities.

Billions of dollars collected and not too much to show for it — sounds like most government run programs.