Last week, the Senate voted 57-40 to confirm Harvard and University of Chicago law professor Cass Sunstein as the new head of the Office of Information and Regulatory Affairs. This narrow vote brought an end to months of overheated and frequently misguided attacks on the would-be "regulatory czar," including a sensationalistic website operated by the American Conservative Union that falsely painted Sunstein as an out-of-control radical.

Too busy making outlandish claims about his positions on gun control and radio censorship, Sunstein's conservative critics have ignored one of the biggest problems that his ideas pose to limited constitutional government. Sunstein is one of the most influential modern critics of Lochner v. New York (1905), perhaps the Supreme Court's most famous decision defending economic liberty. So why aren't conservatives going after Sunstein for his opposition to this case? Because many of them don't like Lochner either.

At issue in the case was a provision capping working hours in New York's 1895 Bakeshop Act, which banned bakery employees from working more than 10 hours per day or 60 hours per week. In its 5-4 decision, the Court nullified this provision for violating the liberty of contract secured by the Due Process Clause of the 14th Amendment.

In his 1987 Columbia Law Review article "Lochner's Legacy," which is one of the most cited articles on the case from the last two decades, Sunstein criticized Lochner for preventing the state from using its lawful power "to help those unable to protect themselves in the marketplace." Similarly, in his 1998 book The Partial Constitution, Sunstein asserted that the Lochner Court "made the system of 'laissez faire' into a constitutional requirement."

But compare those claims with the actual text of the Lochner decision. As Justice Rufus Peckham wrote for the majority, while New York certainly possessed the power to enact valid health and safety regulations, the maximum hours provision of the Bakeshop Act "is not, within any fair meaning of the term, a health law." Not only was the baking trade "not dangerous in any degree to morals, or in any real and substantial degree to the health of the employee," the limit on working hours involved "neither the safety, the morals, nor the welfare, of the public." In other words, "clean and wholesome bread does not depend on whether the baker works but ten hours per day or only sixty hours a week."

Indeed, as Peckham carefully explained, those sections of the Bakeshop Act regulating "proper washrooms and closets," the height of ceilings, floor conditions, and "proper drainage, plumbing, and painting," remained perfectly valid health and safety regulations; only the hours provision was struck down. Moreover, just three years later, in Muller v. Oregon, the Supreme Court unanimously upheld a state law limiting female laundry employees from working more than 10 hours a day. So much for Lochner making "'laissez faire' into a constitutional requirement."

In fact, as George Mason University legal scholar David Bernstein has thoroughly documented, the mainstream version of the Lochner story, which pits evil bosses against viciously exploited workers, bears zero resemblance to the historical evidence. The real origins of the Bakeshop Act lie in an economic conflict between unionized New York bakers, who labored in large shops, and their non-unionized, mostly immigrant competitors, who tended to work longer hours in small, old-fashioned bakeries. As Bernstein observed, "a ten-hour day law would not only aid those unionized workers who had not successfully demanded that their hours be reduced, but would also help reduce competition from nonunionized workers."

To put it another way, Lochner v. New York secured a fundamental right against arbitrary government interference while undercutting an act of naked economic protectionism. Yet Sunstein's right-wing foes haven't mentioned the case in their opposition to his appointment. Why? Perhaps it's because prominent leaders of the conservative legal movement also dislike Lochner.

In his 1991 bestseller The Tempting of America, for example, former federal appeals court Judge Robert Bork denounced Lochner as "the symbol, indeed the quintessence, of judicial usurpation of power," linking it to the Court's later rulings securing privacy and abortion rights under the 14th Amendment. Supreme Court Justice Antonin Scalia routinely attacks the Court's abortion and gay rights rulings for their Lochnerian judicial activism. And during his 2005 Senate confirmation hearings, future Chief Justice John Roberts declared, "You go to a case like the Lochner case, you can read that opinion today and it's quite clear that they're not interpreting the law, they're making the law."

These judicial conservatives aren't necessarily worried about restricting state regulatory power, but they are very leery of the Court protecting unenumerated rights—be it liberty of contract or privacy. Which matches nicely with Sunstein's claim that part of the problem with the Lochner Court was its "aggressiveness" and "judicial intrusions into the democratic process."

Yet both sides ignore the Ninth Amendment, which reads, "the enumeration in the Constitution of certain rights shall not be construed to deny or disparage others retained by the people." Which means we possess more rights than any document could ever list, including the right to earn an honest living free from arbitrary and unnecessary regulation. They also both ignore the Privileges or Immunities Clause of the 14th Amendment, which was specifically designed to protect both civil rights and economic liberties against predatory state governments.

That's the real problem with Cass Sunstein—and with the conservatives who share his hostility towards Lochner. They don't give economic liberty its constitutional due.

Damon W. Root is an associate editor at Reason magazine.