From a libertarian point of view, California Proposition 30 and California Proposition 38 are both bad ideas. They both are tax increases in what is already one of the most heavily taxed states in the country, a state that suffers more than others from Great Depression II. They both claim to do the same thing and for the same goal. But even though they are both bad ideas, one of them is clearly more of a bad idea than the other.
The supporters of Proposition 30 advertise it as a tax increase on the rich. It is true that it does increase income taxes on higher income earners, but it also increases the sales tax. The sales tax is a regressive tax that impacts everyone. The supporters of Proposition 38 advertise it as an income tax increase, which it is. Only the income tax is raised, but it is raised on everyone.
Both of these measures are supposed to be for education, to fund the schools. The monies that might be raised by Proposition 30 go into the general fund and are not dedicated to the schools. The reason school funding is impacted by Proposition 30 is because the legislature and the governor put a trigger in the budget to cut school funding if Proposition 30 is not passed. Proposition 38 dedicates all of the revenue that might be raised to the schools bypassing the general fund.
Given these differences, if someone is inclined to agree with the arguments used to sell these propositions, it makes sense that Proposition 38 would be the preferred ballot measure. While the California PTA prefers Proposition 38, the California teachers unions have come out strongly for Proposition 30.
The unions join the rest of the political classes in favor of supporting Proposition 30. Across the state, the more strongly tied to the unions or the Democratic Party a group is, the more likely it is to support Proposition 30 over 38. The arguments in favor of Proposition 30 are very disingenuous.
Both of these propositions are bad ideas, but it is quite clear that Proposition 30 is a far worse idea than Proposition 38.