For California, 2004 is starting to look like the year of the boutique tax increase. Three measures heading toward the November ballot each seek to secure a relatively narrow slice of income or assets and dedicate it to a favored purpose.

One measure would increase taxes on commercial property and plow the money into funding preschools and teacher salaries. Another would hike an existing phone tax and spend the money on health care, mainly in emergency rooms.

And a third, which already has sufficient signatures to qualify for the ballot, would levy a 1 percent income tax surcharge on million-dollar earners to finance a dramatic expansion of the state's mental health care system.

The mental health tax is sponsored by a coalition of community mental health groups - many funded by government - and Assemblyman Darrell Steinberg, a Sacramento Democrat who has been a leader in setting mental health policy in the Legislature.

The idea behind the measure, Steinberg says, is to fulfill a quarter-century-old promise California made when it emptied its state hospitals and pledged to treat the mentally ill in the community. A lack of funding for those community programs is blamed in part for an increasing number of mentally ill homeless people wandering the streets, creating a danger to themselves and others.

Steinberg's cause may be just, but his method is wrong. His millionaire's tax would extend what is already a bad trend in California, where legislators elected to weigh competing priorities too often have their hands tied by ballot initiatives that offer questions to the public one at a time, without context.

We already have two different tobacco taxes - one for health care and the other for children's programs. Another measure allocates the sales tax on gasoline to road and transit construction. And of course the mother of all voter mandates is Proposition 98, which didn't reserve a specific tax for education but instead dedicated a fixed portion of all tax revenues to the schools.

But even if you think ballot-box budgeting is grand, the idea of a millionaire's tax for mental health is flawed.

First, it's incredibly narrow. Only about 25,000 tax returns filed in California - out of more than 13 million overall - show income greater than $1 million. In the most recent year for which records are available, those returns accounted for about $6 billion in tax paid, about one-sixth of all the personal income tax revenue collected by the state. The $600 million the mental health initiative is estimated to raise would represent a 10 percent surcharge on that income group.

Because there are so few million-dollar earners, the tax revenue they generate is volatile in the extreme. In fact, the rise and fall of their incomes and taxes between 1998 and 2001 is the root of all of California's fiscal problems today. The tax paid by million-dollar earners rose from about $6 billion to $15 billion and then fell back down again during those years, but in the meantime, legislators and former Gov. Gray Davis committed the phantom revenue to ongoing programs and cuts in the foundation of the tax base. The resulting deficit continues to plague the state.

That revenue roller coaster proved difficult enough to manage as part of the $80 billion state general fund. But this ballot measure would hook mental health programs on that same revenue source, making millionaires alone responsible for about one-third of all spending for the care of the mentally ill. That would effectively place some of the most vulnerable people in society at the whim of income swings at the far end of the economic spectrum.

To patch this glaring weakness in their measure, the drafters have included provisions that allow, but do not require, the counties to place some of the new money in reserves as a hedge against the ups and downs of the business cycle. And in case that doesn't work, they want to require counties to continue (forever) serving anyone who gets mental health care through this program, regardless of how much money is raised by the new tax. That means if the tax revenue rises, then plummets again, other programs will have to be cut to make up the difference.

Finally, earmarking tax revenue from millionaires for new spending on a specific purpose would complicate efforts by others to hit up those same top-earners to help close the state's $15 billion gap between projected spending and revenue. The millionaire's surcharge, if approved by the voters, would take its slice from those folks regardless of what else happens. But Democrats in the Legislature are pushing hard to raise taxes on the same people by about 20 percent to help balance the budget. The two combined would mean a 30 percent tax increase for the most successful people in the state.

California desperately needs a comprehensive examination of the services the people demand and the government provides - and the taxing system in place to pay for them. This would be the worst possible time to adopt and lock in another narrowly drawn tax committed to expanding one program in isolation from all the others.