California does not have any tax laws with the formal classification of "Simple Tax," as of 2015. In the context of the state of California, Simple Tax is a private initiative headed by politically active California citizens who want to reform the state's tax code to make it more equitable for all citizens, as described on the website of United Californians for Tax Reform. This nonprofit political group believes that the California state tax code is both unnecessarily complex and unfair, particularly to middle-class citizens who are, according to the initiative, paying more than their fair share of state taxes.
The California Simple Tax Initiative argues that the federal tax code, which levies higher tax rates on individuals making hundreds of thousands of dollars a year than citizens making considerably less than that, is fairer than the state's tax code as of 2015. The group argues that California starts its highest tax rate at incomes of $32,291 for single people and $76,582 for married couples who file jointly, as stated on the group's website. This, it argues, means that middle class people bear the brunt of the state's tax rates, something it believes to be unfair and harmful to California citizens.
United Californians for Tax Reform proposes a tax plan that rectifies this by offering changes such as a single standard deduction below a certain income level and the abolishment of tax loopholes.