Some people never learn like those lawmakers who keep trying to treat members of Congress much more favorably than other taxpayers.

As a case in point, take the effort to repeal or increase the current $3,000 cap on tax deductions that members of Congress may claim for their living expenses in Washington, D.C.Six years ago, Congress abolished this cap only to re-establish it the very next year following a nationwide outcry against the special tax break.

This experience, however, hasn't prevented the House Ways and Means Committee from flirting again with the same ploy.

One argument for the proposed change is that repealing or increasing the cap would merely treat members of Congress the same as businessmen who deduct living expenses. But businessmen normally may deduct living expenses associated with business activities only if those expenses are incurred while the taxpayer is away from home. "Home" is defined for tax purposes as the place the taxpayer has his or her principal place of business.

By contrast, members of Congress are subject to a special provision that defines a lawmaker's home or principal place of business as the state or district the lawmaker represents even though he or she spends much more time in Washington. As a result, members of Congress may take business deductions for what are actually the normal costs of living at home. It is this special provision, enjoyed only by the lawmakers, that has the $3,000 cap.

Another argument for the proposed change is that the $3,000 cap has not been adjusted for inflation since 1954. But the cap limits a tax break that is highly questionable to begin with.

Members of Congress already enjoy plenty of costly favors. They don't need or deserve another big break at the expense of other taxpayers.