Is the individual mandate at the heart of "ObamaCare" a conservative idea? Is it constitutional? And was it invented at The Heritage Foundation? In a word, no.

The U.S. Supreme Court will put the middle issue to rest. The answers to the first and last can come from me. After all, I headed Heritage's health work for 30 years. And make no mistake: Heritage and I actively oppose the individual mandate, including in an amicus brief filed in the 11th Circuit Court of Appeals to the Supreme Court.

Nevertheless, the myth persists. ObamaCare "adopts the 'individual mandate' concept from the conservative Heritage Foundation," Jonathan Alter wrote recently in The Washington Post. MSNBC's Chris Matthews makes the same claim, asserting that Republican support of a mandate "has its roots in a proposal by the conservative Heritage Foundation." Former House speaker Nancy Pelosi and others have made similar claims.

The confusion arises from the fact that 20 years ago, I held the view that as a technical matter, some form of requirement to purchase insurance was needed in a near-universal insurance market to avoid massive instability through "adverse selection" (insurers avoiding bad risks and healthy people declining coverage). At that time, President Clinton was proposing a universal health care plan, and Heritage and I devised a viable alternative.

My view was shared at the time by many conservative experts, including American Enterprise Institute (AEI) scholars, as well as most non-conservative analysts. Even libertarian-conservative icon Milton Friedman, in a 1991 Wall Street Journal article, advocated replacing Medicare and Medicaid "with a requirement that every U.S. family unit have a major medical insurance policy."

My idea was hardly new. Heritage did not invent the individual mandate.

But the version of the health insurance mandate Heritage and I supported in the 1990s had three critical features. First, it was not primarily intended to push people to obtain protection for their own good, but to protect others. Like auto damage liability insurance required in most states, our requirement focused on "catastrophic" costs — so hospitals and taxpayers would not have to foot the bill for the expensive illness or accident of someone who did not buy insurance.

Second, we sought to induce people to buy coverage primarily through the carrot of a generous health credit or voucher, financed in part by a fundamental reform of the tax treatment of health coverage, rather than by a stick.

And third, in the legislation we helped craft that ultimately became a preferred alternative to ClintonCare, the "mandate" was actually the loss of certain tax breaks for those not choosing to buy coverage, not a legal requirement.

So why the change in this position in the past 20 years?

First, health research and advances in economic analysis have convinced people like me that an insurance mandate isn't needed to achieve stable, near-universal coverage. For example, the new field of behavioral economics taught me that default auto-enrollment in employer or nonemployer insurance plans can lead many people to buy coverage without a requirement.

Also, advances in "risk adjustment" tools are improving the stability of voluntary insurance. And Heritage-funded research on federal employees' coverage — which has no mandate — caused me to conclude we had made a mistake in the 1990s. That's why we believe that President Obama and others are dead wrong about the need for a mandate.

Additionally, the meaning of the individual mandate we are said to have "invented" has changed over time. Today it means the government makes people buy comprehensive benefits for their own good, rather than our original emphasis on protecting society from the heavy medical costs of free riders.

Moreover, I agree with my legal colleagues at Heritage that today's version of a mandate exceeds the constitutional powers granted to the federal government. Forcing those Americans not in the insurance market to purchase comprehensive insurance for themselves goes beyond even the most expansive precedents of the courts.

And there's another thing. Changing one's mind about the best policy to pursue — but not one's principles — is part of being a researcher at a major think tank such as Heritage or the Brookings Institution. Serious professional analysts actually take part in a continuous bipartisan and collegial discussion about major policy questions. We read each other's research. We look at the facts. We talk through ideas with those who agree or disagree with us. And we change our policy views over time based on new facts, new research or good counterarguments.

Thanks to this good process, I've altered my views on many things. The individual mandate in health care is one of them.

Stuart Butler, Ph.D., is a distinguished fellow at the Heritage Foundation