But supporters of a pure flat-rate income tax say various studies — and history itself — show that doing away with the mortgage interest deduction doesn't harm housing markets and eliminating the charitable deduction doesn't harm charitable giving, either.

Brigham Young University business professor Gary Cornia, who was part of the tax-reform study group put together last year by former Gov. Olene Walker that recommended a flat-rate tax, told the new Tax Reform Task Force on Thursday that a number of studies from around the world show that doing away with those deductions has little or no impact on how society operates in those areas.

In fact, said Cornia, studies show that economies actually grow when tax systems are reformed to broaden the tax base while lowering the tax rate.

A true flat-rate income tax taxes citizens on their adjusted gross income — with no deductions taken — explained Cornia. "I know," he said, "people say wait a minute: 'Not allow deductions for home mortgages or charitable giving?' "

But Utah has a warped flat-rate system now, the experts explained. While the rates vary from 2.3 percent to 7 percent, the top rate kicks in for income over $8,626 for a married couple, and so almost all Utahns are in that top 7 percent bracket.

Going to a true flat-rate system will allow that top rate to be cut to around 4 percent — and the savings to all taxpayers in money, simplicity and understanding of the income tax system makes up for doing away with the deductions, Cornia and other Walker tax study members said.

The problem, of course, is one of citizen understanding and political impacts.

"Remember," said Utah State Tax Commission member Bruce Johnson, who also sat on the Walker panel, "you would still get the deductions on your federal income tax returns" — you just wouldn't get them on your state returns.

Broadening the state sales-tax base to include personal services — like haircuts and lawn care — and health-care bills would also allow the sales tax rate to be lowered, the experts said.

Paying the sales tax on most services would allow the state's current rate of 4.75 percent to be cut to 3.75 percent, the Walker panel said.

Finally, after the Walker panel noted that low-income Utahns would be exempt from a flat-rate income tax as they are under the current system, task force member Rep. John Dougall, R-Highland, asked why low-income Utahns should avoid paying "even a small tax." "Aren't we making a welfare program part of a tax system?" he said.

Perhaps, the experts said.