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.
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.
Is Drug Testing Welfare Applicants Unconstitutional? - Yahoo! News