As reported yesterday in the New York Times , over the past year three dozen states introduced legislation to drug test individuals receiving public assistance. This includes individuals applying for everything from Temporary Assistance for Needy Families (TANF) to welfare, unemployment and Medicare. (Incidentally, you know who isn't being asked to submit to drug testing before receiving public assistance? Bankers, traders and anyone else who received money from the bailout.)

Thankfully, most of these bills have failed, but not all of them have. The most pernicious of them all was passed and was signed into law in Florida and more limited requirements were added in Indiana, Missouri and Pennsylvania . Florida's bill goes so far as to make all people applying for public assistance — who by definition have very limited means — pay for the cost of their drug test. If an individual's drug test comes back negative, the state will then reimburse the cost of the test. If the drug test comes back positive, Florida will bar the applicant from reapplying for TANF for a year (unless they get counseling, in which case they can apply in 6 months). There are no plans to offer any sort of substance abuse counseling or rehabilitation.

These laws are wrong. They are flat-out unconstitutional , shortsighted and will end up costing the state more than any possible savings . But even putting all of that aside, let's stop for a moment and ask ourselves the bigger question of why. Why are we drug testing anyone who isn’t flying an airplane? Why poor people in particular? Some might argue it’s because we can’t have people spending money from the federal government on drugs. But I haven’t heard of any plan to start drug testing students at Harvard who get federal student loans. These laws deliberately separate poor people from the rest of society, asserting that they have less of a right to privacy simply because they are having trouble making ends meet.

Others might argue that people are drug tested for their jobs, so why shouldn’t people have to get tested to receive benefits? Because expanding the indignity of mandatory drug testing to more and more people is not the answer. Employers should not require employees to prove their innocence by taking a drug test any more than the government should be forcing poor people to do the same. Mandatory drug testing, whether as a condition of employment or as a requirement for the receipt of public assistance, is an unnecessary intrusion into personal privacy.

Last month, the ACLU of Florida filed suit in federal court on behalf of Luis Lebron, a 35-year-old Navy veteran, father of a 4-year-old, the sole caregiver for his disabled mother and a student at the University of Central Florida who refuses to relinquish his Fourth Amendment rights by submitting to drug testing at the hands of the state. As he said, “I served my country, I’m in school finishing my education and trying to take care of my son. It’s insulting and degrading that people think I’m using drugs just because I need a little help to take care of my family while I finish up my education.”

These laws target people who have one defining characteristic — they are poor . In a time when more and more Americans need help feeding and clothing their families, the last thing we need are laws forcing poor people to give up their most basic constitutional rights.

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