Q: How was the law changed to impose an income tax in the U.S., and in what year was it passed?

A.H., Memphis, Tenn.

A: America's federal income tax has a long and stormy history. Here is a mercifully short summary:

Early in the Civil War, President Lincoln signed into law an income tax to help pay for the war. It survived for a decade. In 1894, lawmakers brought back an income tax. But the Supreme Court struck it down as unconstitutional in 1895.

In 1913, the 16th Amendment to the Constitution "empowered Congress to impose an income tax, and it quickly did so," wrote Michael J. Graetz, now a Columbia Law School professor, in a 1997 book on the income tax. That amendment said Congress "shall have power to lay and collect taxes on incomes, from whatever source derived, without apportionment among the several States, and without regard to any census or enumeration."

You can find a copy of the first Form 1040—and other aspects of tax history, including tax returns filed by many presidents—on the website of Tax Analysts (www.taxanalysts.com), a nonprofit organization. Click on "Tax History Project."

Some people still claim that the federal income tax is somehow voluntary, that wages aren't really "income," or that the 16th Amendment wasn't properly ratified. Even if you believe these arguments, don't try citing them as a reason for not paying your tax. That's a great way to attract attention from the Internal Revenue Service. Courts routinely reject these theories, and you may pay stiff penalties.

"To suggest that it (the 16th Amendment) was not lawfully ratified—or suggest that it doesn't mean what it says it means—is akin to signing up for the Flat Earth Society," says Joseph J. Thorndike, contributing editor and historian at Tax Analysts.

For an idea of what the IRS considers to be frivolous, including legal citations for its position, go to the IRS site (irs.gov). Type "frivolous" in the search box, and click on "The Truth About Frivolous Tax Arguments."
