In fact, Illinois is one of only three states in the country to completely exempt pension income from income tax, one of a dozen that do not tax retirement income and one of 27 that do not tax Social Security benefits.

Read: 10 least tax-friendly states

But, considering that the state has been operating without a budget for almost the past six months and is running out of ideas to raise cash to continue to fund operations, lawmakers are now looking, albeit out of the corners of their eyes, at seniors' wallets.

Read: 10 scary retirement statistics

Seniors, needless to say, are not happy about the possibility, with AARP already taking the offensive against such a plan and pointing out that the impressive array of taxes already taking a bite out of retirees' income is hefty enough—in fact, Illinois' property taxes are second only to New Jersey's in the country.

And we've already pointed out that in health care costs alone, Illinois ranks right up there—pardon me, down there—among the 10 most expensive states in the nation.

Editorials are taking both sides, with some claiming that budgetary fiscal responsibility can only be achieved—and, in fact, it is only fair to do so—by taxing seniors.

Others decry the idea of such a tax being fair, stating that it would hit a segment of the population that is mostly out of the workplace and thus unable to replace retirement income lost to a new tax.

They also loudly point out that such a tax could cause an exodus of seniors from the state—or, at the very least, result in substantially curtailed spending by the ones who remain, thus cutting everyone else's incomes as businesses lose customers.

Of course, there are many ways to implement such a tax, should the legislature opt to do so—taxing just Social Security, taxing just pension or 401(k) income, or taxing some mix of the above, or even making it contingent on the level of income or amount of other income seniors may be receiving.

But one thing is sure: it's going to be a noisy discussion.