[Tublecane]

You just named two different rules for different ranges of income. That right there is inequality. You say you haven’t thought through different rates fir different classes of people, as in singles versus marrieds. I’ll fill you in: it’s the same. Different rules, not equal. You find the same thing within the single class. Different rules for different individual incomes. Once again, inequality.

I don’t know how plainer I can make it. Would it help if instead of above and below $17400 dollars we said 10%for whites and 15% for blacks?

[DaveInDallas]

That right there is inequality.

No it's not. Everyone is subject to the same rates for the same income. All married couples pay the same rate for income in each bracket, so there is no equal protection violation. It's been that way since 1913.