â€œDemocracies choose bad policies because bad policies are popular,â€ writes Bryan Caplan in a recent edition of Cato Journal, â€œand bad policies are popular because voters have systematically biased beliefs about their effects.â€ The piece in which that apothegm appears concerns immigration, which is fitting.

Americansâ€"conservative Americans particularlyâ€"think America will be better off if it fiercely guards its borders, allowing only a few people of the more desirable sort to cross them. They are mistaken. Not only does a generous immigration policy improve life for people already here, a hawkish immigration policy also can have serious downsides for U.S. citizens.

Economically, the case for more immigration is compelling: Immigrants are more likely than native-born Americans to start a business, more likely to launch a hugely successful one, more likely to work and less likely to commit crime. Free trade increases prosperity, and that is just as true of trade in labor as for goods. (Caplan cites research estimating that â€œopen borders would roughly double world GDP, enough to virtually eliminate global poverty.â€)

Morally, the case for easing restrictions on immigration is compelling as well. Government has no more justification restricting the free movement of people than it has restricting the free movement of products or services. A tight-border policy denies native-born Americans the opportunity to hire, work for, sell to, lease to, make friends with, and even marry individuals they would freely do those things with if they could. A tight-border policy also consigns countless opportunity-seeking individuals to life in countries that are poorer and less free than the United States.

Granted, not everyone cares about the effect of immigration policy on other people. But there are sound, self-interested reasons to oppose tight border control as well.

According to Gallup, 85 percent of Americans support requiring employers to verify that all new hires are living in the U.S. legally. This likely is owing to the false belief that illegal immigrants take jobs that â€œbelong toâ€ Americans. That belief is false for three reasons: First, jobs donâ€™t belong to anyone but the person doing the hiring. Second, illegal immigrants often do work Americans refuse to do. Third, Americans donâ€™t just give jobs to undocumented workers. They also take money from them by selling them food and clothing, renting apartments to them, and so forth. That commerce creates jobs forâ€"yep â€"Americans.

Whatâ€™s more, trying to stop illegal immigrants from finding jobs could keep Americans from finding them, too. In a recent piece for The Wall Street Journal, Laura W. Murphy of the liberal ACLU and Fred L. Smith, Jr. of the conservative Competitive Enterprise Institute explain that the E-Verify system is riddled with holes. Moreover, â€œif an employeeâ€™s information conflicts with the database, the individual cannot work until he corrects the error. Every potential employee is thus presumed to be ineligible to work until proven otherwise.

They note a 2009 Homeland Security report showing that a national E-Verify system â€œwould force 1.2 million of todayâ€™s legal workers to sort out such problems. Of these, almost 770,000 genuinely legal workers would lose their jobs.â€

Conservatives, especially of the Tea Party variety, should be alarmed by the prospect of having to get a permission slip from the federal governmentâ€"a government they consider as efficient as the Postal Service and as compassionate as the IRS â€" before exercising the right to earn a living. That is just one part of the price to pay for the dubious benefit of â€œsecuring the border.â€

The gutting of the Bill of Rights is another. Since 2008, the Department of Homeland Security has claimed the right to seize and search your electronic belongingsâ€"cell phone, laptop, etc. â€"at the border, without a warrant and without even any suspicion of wrongdoing.

But not just at the border: DHS claims the authority to conduct warrantless electronic searches within 100 miles of the U.S. border. That covers 197 million peopleâ€"almost two-thirds of the American population. What constitutional authority does DHS have to disregard the Fourth Amendment this way? Thatâ€™s classified, it says. While the agency has released an executive summary of its rationale, the ACLU had to file a Freedom of Information Act request on Feb. 8 to see the entire report.

Meanwhile, Homeland Security continues to put its policy into practice. Without any suspicion of wrongdoing, it has seized the electronic devices of a computer programmer involved with a legal defense fund for Bradley Manning, a researcher for Wikileaks, and others. (According to an October lawsuit filed by the ACLU of San Diego, border agents also have seized cameras from photographers who were simply taking photographs in publicâ€"which is is not merely legal, but constitutionally protected.)

Thatâ€™s the trouble with taking a hawkish approach to immigration: The harder you try to keep people outside the fence, the more youâ€™re bound to restrict the freedom of people already inside it. You can have a leak-free borderâ€"or you can have limited government that respects liberty and individual rights. Take your pick.

This article originally appeared at the Richmond Times-Dispatch.