Unfortunately for many lawmakers, the issue of marriage penalties simply won't go away. In the first place, compared to previous decades, there are many more two-earner couples today with earnings that are not widely separated. That adds to the numbers of those hit with penalties every year. Equally important, the number of couples who cohabitate without a marriage license has increased dramatically at all age levels, adding to the sense of inequity among those who are married and pay higher taxes simply because of their vows to each other. In effect, marriage penalties today are voluntary for all except those committed to formal marriage as an institution, sacrament, or way of life.
Many analysts are also lukewarm on marriage penalty relief.
Typically, they note the inevitable problems that arise when one tries to tax households in a progressive tax system. If the system moves toward single filing for all people, then married couples whose incomes are unevenly split would pay more tax than those whose incomes are evenly split. Those who support marriage penalties base their belief partly on economies of scale in marriage. The notion is that two persons living together can live more cheaply than two living apart. The couple needs only one place to live and can get by with one TV and one set of pots and pans.