President Barack Obama
The Buffett Rule has come to embody a central theme of the president's re-election campaign: tax fairness. Reuters

President Barack Obama sent another pointed message to the U.S. Supreme Court Tuesday, noting that the powerful institution has shown significant restraint in dealing with laws passed by Congress in the decades since it overturned Progressive Era and New Deal laws.

In a speech at an annual Associated Press event, Obama again appealed to the high court's reputation as a cautious institution that often defers to Congress when weighing the laws it passed.

Speaking on the topic for the second time since the health care law arguments last week, Obama tempered his tone from Monday, when he said conservative commentators for years had lamented judicial activism or a lack of judicial restraint from an unelected group of people.

Supreme Court is the final say on our Constitution, and all of us have to respect it, Obama said. But it's precisely because of that extraordinary power that the court has traditionally exercised significant restraint and deference to a duly elected legislature.

Still, the president is crafting an election-year message to defend against a possible ruling to overturn his signature domestic achievement, the Affordable Care Act. The Supreme Court could be a foil for the president, like the Republican-controlled U.S. House of Representatives and the GOP minority in the Senate.

Obama linked his situation with the Roberts Court to the conservative court that overturned employment and economic laws passed during the Progressive Era 100 years ago and stymied Franklin D. Roosevelt's New Deal agenda. Those justices served during the Lochner Era, named for a 1905 ruling in which a conservative majority used a narrow interpretation of the Commerce Clause to controversially overturn a New York law limiting bakers' working hours.

The Commerce Clause is the constitutional underpinning of the mandate that most Americans carry a basic level of health insurance -- and of much of the modern federal government.

We have not seen a court overturn a law that was passed by Congress on an economic issue, like health care, that I think most people would clearly consider commerce -- a law like that has not been overturned at least since Lochner, Obama said of the landmark 1905 decision. So, we're going back to the '30s, pre-New Deal.

Obama also said the administration has no backup plan to insure 30 million uncovered Americans in the event the Affordable Care Act or the insurance mandate gets overturned, expressing confidence the Supreme Court will exercise its jurisprudence carefully and find the law constitutional.

As a consequence, he said, we're not spending a whole bunch of time planning for contingencies.