Drug testing the poor is becoming an increasingly popular idea. But not only does it not save money, it's likely to be unconstitutional

Under a new Florida law, people applying for welfare have to take a drug test at their own expense. If they pass, they are eligible for benefits and the state reimburses them for the test. If they fail, they are denied welfare for a year, until they take another test.

Mandatory drug testing for welfare applicants is becoming a popular idea across the U.S. Many states — including Alabama, Kentucky, Oklahoma and Louisiana — are considering adopting laws like Florida’s. At the federal level, Senator David Vitter, a Louisiana Republican, has introduced the Drug Free Families Act of 2011, which would require all 50 states to drug-test welfare applicants.

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And the focus isn’t even limited to welfare. In July, Indiana adopted drug tests for participants in a state job-training program. An Ohio state senator, Tim Grendell, recently said he plans to introduce a bill to require the unemployed to take a drug test before they receive unemployment benefits.

Drug testing the needy has an undeniable populist appeal. It taps into deeply held beliefs about the deserving and undeserving poor. As Alabama state representative Kerry Rich put it, “I don’t think the taxpayers should have to help fund somebody’s drug habit.”

But as government policy, drug testing is being oversold. These laws do not do what their supporters claim. And more importantly: they are likely to be unconstitutional.

Drug testing proponents like to argue that there are large numbers of drug users going on welfare to get money to support their habits. The claim feeds into long-standing stereotypes about the kind of people who go on welfare, but it does not appear to have much basis in fact.

Several studies, including a 1996 report from the National Institute on Alcohol Abuse and Alcoholism, have found that there is no significant difference in the rate of illegal-drug use by welfare applicants and other people. Another study found that 70% of illegal-drug users between the age of 18 and 49 are employed full time.

Drug-testing laws are often touted as a way of saving tax dollars, but the facts are once again not quite as presented. Idaho recently commissioned a study of the likely financial impact of drug testing its welfare applicants. The study found that the costs were likely to exceed any money saved.

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That happens to be Florida’s experience so far. A Florida television station, WFTV, reported that of the first 40 applicants tested, only two came up positive, and one of those was appealing. The state stands to save less than $240 a month if it denies benefits to the two applicants, but it had to pay $1,140 to the applicants who tested negative. The state will also have to spend considerably more to defend the policy in court.

Given that cost-benefit reality, it is hard to escape the suspicion that what is really behind the drive to drug-test benefits applicants is a desire to stigmatize the needy. The fact is, there are all sorts of people who benefit from government programs. Businessmen get state contracts, farmers receive crop subsidies and retired state workers receive pensions. The pro-drug-testing movement, however, is focusing exclusively on welfare recipients — an easy target.

Policies like Florida’s will almost certainly end up in court — and there is a good chance that they will be struck down. The Fourth Amendment puts strict limits on what kind of searches the state can carry out, and drug tests are considered to be a search. In 1997, in Chandler v. Miller, the Supreme Court voted 8-1 to strike down a Georgia law requiring candidates for state offices to pass a drug test.

Justice Ruth Bader Ginsburg, writing for the majority, said that the drug testing was an unreasonable search. The state can impose drug tests in exceptional cases, when there is a public-safety need for them (as with bus and train operators, for instance). But the Fourth Amendment does not allow the state to diminish “personal privacy for a symbol’s sake,” the court said.

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Drug testing welfare applicants does not seem to meet the Chandler test since there is no particular safety reason to be concerned about drug use by welfare recipients. In 2003, the U.S. Sixth Circuit Court of Appeals struck down Michigan’s drug testing of welfare applicants as a Fourth Amendment violation.

If Florida and other states are really concerned about drug use, they should adopt stricter laws and better enforcement policies aimed at the whole population, not just the most vulnerable. But these laws are not really about drug use. They are about, in these difficult economic times, making things a little harder for the poor.