No Respite for Liberals - NYTimes.com ANTON CHEKHOV once remarked that "one must not put a loaded rifle on the stage if no one is thinking of firing it." In the term that ended last week, the Supreme Court reached a liberal outcome in cases involving President Obama's health care law, Arizona's draconian immigration statute and mandatory life sentences for juveniles. But the conservative majority also laid down a cache of weapons that future courts can use to attack many of the legislative achievements of the New Deal and the Great Society - including labor, environmental, civil rights and consumer protection laws - and to prevent new progressive legislation. Far from being a source of jubilation, the term may come back to haunt liberals. The immediate result of Thursday's 5-to-4 health care ruling was a victory for the Obama administration and the millions of Americans who will get improved access to medical care. But four justices would have struck down every provision of the 900-plus-page act, and Chief Justice John G. Roberts Jr., who provided the fifth vote to uphold the mandate that individuals buy insurance or pay a penalty, distanced himself from the law. "It is not our job," he wrote, "to protect the people from the consequences of their political choices." The chief justice, who at 57 is likely to sit on the court for at least another two decades, made clear that government's ability to address many of the nation's most pressing problems is subject to some new limitations. We take for granted that the federal government can forbid landlords to reject a tenant based on his race or religion; prohibit development on fragile wetlands; finance the Medicare program for the elderly; require public schools to give girls an equal opportunity to play sports; collect revenue to pay for the National Institutes of Health and the national parks; encourage energy conservation by taxing gas guzzlers; prohibit discriminatory voter ID laws; and vindicate the right of state government employees to take unpaid leave to care for sick relatives. The conservative legal movement has already attacked many of these provisions, and the Roberts court has been steadily supplying it with ammunition to do so. Conservative judicial rhetoric - for example, Justice Antonin Scalia's denunciation last week of the Obama administration's decision not to deport young, law-abiding illegal immigrants who came to this country as children - may be designed to change the political climate as well. The federal government's ability to regulate economic and social life stems largely from four powers in the Constitution. Under the commerce clause, Congress can "regulate" national economic activity. Under the taxing power, it can "lay and collect Taxes." Under the spending power, it can "provide for the common Defence and general Welfare of the United States." And under the enforcement powers, it can enact "appropriate legislation" to enforce the 14th Amendment's equal protection and due process clauses and the 15th Amendment's guarantee of the right to vote regardless of race. From the 1930s through the Warren and Burger courts, the Supreme Court largely deferred to the political branches" judgments about the scope of these powers; it was their partner, not their adversary. The court recognized - as Justice Ruth Bader Ginsburg pointed out in her opinion on the health care case - that the political process was the primary vehicle for limiting government's powers. Under the last chief justice, William H. Rehnquist, the court began to turn, particularly on Congress's commerce and enforcement powers. The court limited some statutes - notably, a section of the Americans With Disabilities Act that allowed state workers to sue their employers and a section of the Violence Against Women Act that gave victims of gender-motivated violence the right to sue in federal court - but upheld others, including other applications of the disabilities law, a provision of the Family and Medical Leave Act, and a statute criminalizing possession of homegrown marijuana. Pamela S. Karlan is a professor of public interest law at Stanford and a co-author of "Keeping Faith With the Constitution."